Cursorcreate

- Fixed a path resolution bug which was causing themes not to build correctly when working in the directory of the project and executing the build from the command line.

- Added setup.py.
- Moved all source code into directory 'CursorCreate'.
- Added PyPI Package.

- 24px by 24px export size was removed from the Linux exporter due to some software always selecting the smallest cursor size.
- Minimized calls to `copy.deepcopy` to help with memory usage.

- Fixed a memory leak, all dialogs are properly garbage collected now when closed.

Update includes an overhaul to the Linux and Windows builders, and also some bug fixes:

- Linux builder now builds theme in a tar.gz file, meaning themes can be built for Linux even on platforms/file systems that do not support symlinks
- Windows builder builds theme into a zip archive so it is easier to deploy and distribute.
- Bug fixed that would cause animation timers to continue running even after a dialog was closed.

The following features have been added to CursorCreate:
- A preview dialog, which allows for cursors to be seen while editing them.
- A new exporter called "preview-picture". Generates a PNG showcasing all of the cursors in the theme. Can be placed on a artist designed background and used when showcasing the cursor theme online.