[2.0.6] Improved offline ctbans with custom duration and reason support, minor changes

• Improved sm_ctban_offline command by supporting a custom duration and reason
• Added quotes ("") support for sm_ctban_offline, sm_unctban_offline (as well as its alias sm_unctban_offline) and sm_isbanned_offline. Previously, quotes weren't removed properly.
• Improved code visibility in some places
• Fixed a bit the french translations

Note: Writing the SteamID between double quotes (") is now needed for sm_ctban_offline.
Here is the new syntax: sm_ctban_offline <"steamid"> <optional: time> <optional: reason>
Examples (these are all valid):
sm_ctban_offline "STEAM_1:1:57298004" 60 "Freekill, doesn't know the rules"
sm_ctban_offline "STEAM_1:1:57298004" 60 Freekill, doesn't know the rules
sm_ctban_offline "STEAM_1:1:57298004" 60
sm_ctban_offline "STEAM_1:1:57298004"
However, this isn't valid: sm_ctban_offline STEAM_1:1:57298004

Note 2: sm_ctban_force_reason isn't enforced for sm_ctban_offline. The reason is always optional.

Note 3: I might do the same thing for Rage Bans, but offline CT bans with custom durations and reasons are supported now, so it isn't my top priority.

Warning: This release was bugged, and is now fixed with this commit. If you downloaded it within 5 hours of its release, you need to update it again! The bugged release was replaced by the fixed and final 2.0.6 in this release, so you can download it safely.