Merge pull request #406 from sergeyklay/master

Cerber Theme updates
Fixed issue: Fixed typo in welcome text
New feature: Added Estonian translation

Thanks to Sergei Moroz
New feature: WIP. Created settings for the forced change of locale
Updated feature: Added Estonian
Merge pull request #407 from sergeyklay/fixes

Fixed typo in welcome text
Merge pull request #408 from sergeyklay/i18n

Estonian support
Fixed Issue #405: Proper active link css class
Update feature: Proper locale init and timezone,needs lot of work and tetsing; WIP.
Update feature: Allow locale override settings and locale detection; WIP
Update feature: Locale and timezone detection with respect to guest user; WIP
Updated feature: Gleez environment refactoring
Updated feature: Amended install guide
Updated feature: Updated database.php template
Updated feature: Updated Database schema for all languages