Merge pull request #14 from aportale/master

Improving the copy behaviour of the display widget
Restore window maximization properly on launch

https://code.google.com/p/speedcrunch/issues/detail?id=461

Only the window size and position have been restored. When the window is
maximized on exit, the window position can be off on restore on some systems
(e.g. Ubuntu).
Add test for known issue about right to left exponentiation

https://code.google.com/p/speedcrunch/issues/detail?id=448
Not using PNG compression in ICO, in order to support WinXP