Now the default configuration tries to set the language from the system
locale, and defaults to english if no language match.

This closes #473.
Minor cosmetic changes
Fix printing ipv6 addresses with identd

Closes #639
Add completion_amount to prefs

... and remove completion_auto which is confusing to say the least.
Emit FOUNDIP in server session
Specify what for completion amount
Add irc_ban_type to preferences
Merge pull request #640 from orium/default-language

Default language