Add error_codes to __all__.
Standardise on lists rather than tuples for __all__.
Added function that's implicit in the EGL spec and made more explicit in the surfaceless extension.
Fixed extension loading from the new, flattened structure.
Fixed copyright dates for files modified this year.
Corrected name of swap_interval property.
Fixed some errors in using or referring to release_thread().
Oops, no, release_thread() is not a method of Display.
Split stream extensions into properly separated modules.
Merged changes from develop branch.
Added extension module to __all__.
Merged one more change from develop branch.
Added mention of another extension that won't be supported.
Added the official version of Nokia's swap_region extension.