Implementation of ENG Formula Editor Keyboard

# New positioning of keys on keyboard.
# Strings.xml update with english keyboard strings.
# Redo-Undo buttons move from actionbar to keyboard.
# Refactor of ScriptTabActivity, FE-Fragment, LookFragment
  and LogicFragment.
Increasing the key width of numbers.
Raw implementation of MathFragment.
Raw implementation of SensorFragment.
Android sensor-api implemented
Merge branch 'FormulaEditorFragments2MultiLanguageIssue8.53c_8.56c_8.62c_8.65c' of https://github.com/Catrobat/Catroid.git into FormulaEditorFragments2MultiLanguageIssue8.53c_8.56c_8.62c_8.65c
Orientation sensor implemented
Method(getRotationMatrixFromVector) imported from
android.hardware.SensorManager in order to support API-Level < 9
Implementation of FormulaEditorListFragment

# FormulaEditorListFragment summarizes other Fragments (Logic, Look,
Math and Sensor) in one general Fragment.
# update of strings.xml
# update of formula editor keyboard
Merge remote-tracking branch 'origin/FormulaEditorFragments2MultiLanguageIssue8.53c_8.56c_8.62c_8.65c' into FormulaEditorIssues8.53_8.56_8.62_8.65
error fix
Raw implementation of FormulaEditorVariableListFragment.
SensorTest adapted
Sensor values renamed, tests adapted
Sensor rename,
Radian to degree conversion
rotation arround the axis - sensor adaptions,
compute dialog implementation
Delete item added in optionmenu.
Merge branch 'FormulaEditorIssues8.53_8.56_8.62_8.65' of https://github.com/Catrobat/Catroid.git into FormulaEditorIssues8.53_8.56_8.62_8.65
orientation sensor rename
fixed multi formula interpretations when compute is pressed and the
formula doesn't contain any sensor-values
Parameter of functions will be saved if function gets replaced