Implement animated main menu

[Q_x]

Implement an animated main menu that supports the following states for buttons:

• plain: button state when none of the states below apply
• hovered: button state when either the mouse hovers over it or the button is selected via the keyboard (only one button can be selected at a time)
• pressed: button state when it's pressed
• disabled: button state when you can't press the button for whatever reason there may be; e.g. the continue button can't be pressed if you fire up PARPG for the first time

Use case

• The main manu should be show when PARPG is started.
• Furthermore it should be displayed whenever the user presses <ESC>. Right now a placeholder menu is shown when <ESC> is pressed.

[Q_x]

One more thing: Nice if a priviliged person change Component value to "graphics", as I'm not allowed to do it. First ticket in my life. Errare humanum est. Detailed description went to README.txt

Thanks, Luke

[Q_x]

menu.2.png should replace menu.png. Please note I was unable to do it on m own :) It looks much better now and tis 120 pix taller. Also new button "Continue" (6 n/c/h .png) was added as discussed at forums.

[luke]

all needed graphics

[luke]

The menu is implemented. There is only a need for making a picture as the background.