Removed InfoPanel and ColorPanel references
Removed JFileChooser references (now using FileDialog)
Changed "about"
Fixed accelerators and mnemonics
Started undo support and UML diagrams. Fixed accelerators and shortcuts
Deleted undo skeleton files, more work on UML diagrams.
Merge branch 'master' into spreadsheet

Conflicts:
	src/br/ufrn/musica/calendala/controller/MainController.java
	src/br/ufrn/musica/calendala/gui/MainFrame.java
	src/br/ufrn/musica/calendala/gui/MandalaPanel.java
	src/br/ufrn/musica/calendala/gui/MenuBar.java
	src/br/ufrn/musica/calendala/io/FileIO.java
	src/br/ufrn/musica/calendala/mandala/Group.java
	src/br/ufrn/musica/calendala/mandala/Mandala.java
	src/br/ufrn/musica/calendala/mandala/Ring.java
	src/br/ufrn/musica/calendala/mandala/Slice.java