Implement new features

* Update copyright years
* Reload autotexts, dictionaries and keyboard layout maps automatically
* Use BeQt 3.1.0
* Add automatic encoding detection option
Implement new features
TeX Creator v3.1.0-beta

* Update copyright years
* Update README
* Reload autotexts, dictionaries and keyboard layout maps automatically
* Implement new version check
* Use BeQt 3.1.0
* Use TeXSample 1.1.0
* Add automatic encoding detection option
* Reimplement login dialog using BLoginWidget class