Menu mnemonics #51

Added Toolkit.setMenuMnemonics(JMenuItem...) and
Toolkit.setMenuMnemonics(JMenuBar).
Finalize #51 fix
Update Editor.java

Null-check.
Update Toolkit.java

Spacing as requested
Update Toolkit.java

Javadoc bug
Menu mnemonic bug fix

I just found out that jmi.getText() can be null, so I added null-checking.
Merge branch 'master' of https://github.com/processing/processing into mnem-patch

Not quite done yet - temporary commit.
Conflicts:
	app/src/processing/app/Editor.java
	app/src/processing/app/Mode.java
	app/src/processing/app/Toolkit.java
Menu mnemonics merge

Merge menu mnemonics back with current code and integrate with PDE-X.
Finalise menu mnemonics

Added Toolkit.setMenuMnemsInside(); removed Editor.resetMenuMnemonics(); added mnemonics to sketches in Sketch menu.
Merge branch 'master' of https://github.com/processing/processing into mnem-patch

Conflicts:
	pdex/src/processing/mode/experimental/DebugEditor.java
Fix tiny German menumnemonics bug.
Translate cut and copy in the edit menu.

Also condense some code.
Merge pull request #2382 from GKFX/mnem-patch

Dynamically add menu mnemonics to all menus