Trying to install Foreman on a fresh Debian Jessie failed as follow. From this point, I don't really know how to debug this kind of installation. Help is appreciated.

Take note, the locale on this server is "LANG=en_CA.UTF-8".

$ sudo foreman-installer
Installing             -otice: /AddIcon /icons/odf6odm-20x22.png .odm            [4%] [.....                                                                                                                        Error executing SQL; psql returned pid 31265 exit 1: 'ERROR:  invalid locale name: "en_US.utf8" 
'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util/errors.rb:106:in `fail'
/usr/share/foreman-installer/modules/postgresql/lib/puppet/type/postgresql_psql.rb:25:in `sync'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:236:in `sync'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:134:in `sync_if_needed'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:88:in `block in perform_changes'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:87:in `each'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:87:in `perform_changes'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/resource_harness.rb:21:in `evaluate'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:224:in `apply'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:240:in `eval_resource'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:163:in `call'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:163:in `block (2 levels) in evaluate'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util.rb:386:in `block in thinmark'
/opt/puppetlabs/puppet/lib/ruby/2.1.0/benchmark.rb:294:in `realtime'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util.rb:385:in `thinmark'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:163:in `block in evaluate'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/graph/relationship_graph.rb:118:in `traverse'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction.rb:154:in `evaluate'
/usr/lib/ruby/vendor_ruby/kafo/modules/kafo_configure/lib/puppet/parser/functions/add_progress.rb:31:in `evaluate_with_trigger'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/resource/catalog.rb:222:in `block in apply'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util/log.rb:155:in `with_destination'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/transaction/report.rb:137:in `as_logging_destination'
/usr/lib/ruby/vendor_ruby/kafo/modules/kafo_configure/lib/kafo/puppet/report_wrapper.rb:34:in `method_missing'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/resource/catalog.rb:221:in `apply'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/configurer.rb:171:in `block in apply_catalog'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util.rb:223:in `block in benchmark'
/opt/puppetlabs/puppet/lib/ruby/2.1.0/benchmark.rb:294:in `realtime'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util.rb:222:in `benchmark'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/configurer.rb:170:in `apply_catalog'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/configurer.rb:343:in `run_internal'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/configurer.rb:221:in `block in run'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/context.rb:65:in `override'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet.rb:241:in `override'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/configurer.rb:195:in `run'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application/apply.rb:350:in `apply_catalog'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application/apply.rb:274:in `block in main'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/context.rb:65:in `override'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet.rb:241:in `override'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application/apply.rb:225:in `main'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application/apply.rb:170:in `run_command'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application.rb:344:in `block in run'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util.rb:540:in `exit_on_fail'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/application.rb:344:in `run'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util/command_line.rb:132:in `run'
/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/util/command_line.rb:72:in `execute'
/opt/puppetlabs/puppet/bin/puppet:5:in `<main>'
 /Stage[main]/Foreman::Database::Postgresql/Postgresql::Server::Db[foreman]/Postgresql::Server::Database[foreman]/Postgresql_psql[Create db 'foreman']/command: change from notrun to CREATE DATABASE "foreman" WITH OWNER="foreman" TEMPLATE="template0" ENCODING='utf8' LC_COLLATE='en_US.utf8' LC_CTYPE='en_US.utf8'  failed: Error executing SQL; psql returned pid 31265 exit 1: 'ERROR:  invalid locale name: "en_US.utf8" 
'
Installing             Done                                               [100%] [...............................................................................................................................]
  Something went wrong! Check the log for ERROR-level output
  * Foreman is running at https://testfm.patrikdufresne.com
      Initial credentials are admin / zwCbiCH6c4R3V7M4
  * Foreman Proxy is running at https://testfm.patrikdufresne.com:8443
  * Puppetmaster is running at port 8140
  The full log is at /var/log/foreman-installer/foreman.log