Refactor NewVariableDialog. Still a mess!

* Moved all Dialog logic into its own .java file
* Removed code that manually changed Button text color and EditText
  background color.
* Change RadioGroup orientation to vertical, as per discussion with
  Design Team.
* Removed hardcoded string.
* This class needs a lot more love.
Fix testcases that used hardcoded String
Fix tests related to colors and Button state
changed xml of PointIntoDirectionBrick

double --> Formula
removed dialog
fixed tests
removed strings
removed comment
Merge pull request #255 from Catrobat/PointBrickXML

Point brick xml
renamed clickable to enabled
set button final
Merge pull request #253 from Catrobat/NewVariableDialogFix

Refactor NewVariableDialog. Still a mess!
Merge remote-tracking branch 'origin/master' into FEFragmentLintErrorFix

Conflicts:
	catroid/src/org/catrobat/catroid/ui/fragment/FormulaEditorVariableListFragment.java