Added classes for Language database manipulation

Language management

* Added class DBOject to be an interface to interact with all database tables
* Added class Language to manipulate the languages table
* Added language
Merge branch 'develop' of https://github.com/croscato/CodeMess into develop

Conflicts:
	src/dialogs/codemess.cpp
	src/dialogs/languagedlg.cpp
	src/dialogs/languagedlg.h