Add new common header for autofree, etc.
panel: Convert all applets to use autofree
session: Use autofree in dialog
Update HACKING with "autofree" notes
Style: Use correct pointer style, globalise string method
Consistent main() methods (gint, not int, etc)
Generate data/budgie-desktop.desktop file

If prefix is different than /usr, Exec and TryExec path will be broken

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Fixed indentation only
Signed-off-by: Ikey Doherty <ikey.doherty@gmail.com>