Fix string constants in database
Fix database queries errors
Add save new content to local database
Implemented basic upload to server. Works only partially - needs fixing!
Implemented sync with Parse for adding and deleting words and meanings
Merge branch 'master' into ershov

* master:
  Added user menu buttons on main screen.
  Registration and login implemented.
  Some file structure organisation.
  Back buttons implemented

Conflicts:
	src/Erundopel/Erundopel/AddContentChooseViewController.m
	src/Erundopel/Erundopel/AddContentChooseViewController.xib
Adjust log in/out buttons in MainMenuVC
Extract SQL DB initialisation code to a resource file
Merge branch 'master' into ershov

* master:
  Picture resources and settings screen GUI.
  Little refactoring,
  Record fixed. Now statistics is properly saved and restored without stashing.
  Records table implemented.

Conflicts:
	src/Erundopel/Erundopel.xcodeproj/project.pbxproj