Most of the changes that happened after commit 8bbc0d40 broke epoxy
pretty much irreparably because of the CMake build and the attempt at
making libepoxy a static library that can be copy-pasted into another
project without generating files.
Since all the commits are entangled, and are full of unrelated changes,
we cannot simply do a localized set of reverts; instead, we need to hit
the reset button.
From this point forward, we're going to improve libepoxy's build while
attempting to keep the existing build system working. This may mean
reinstating the CMake build system at a later date.
This increases the size of the library, but avoids some of the
concerns that have been brought up with the library silently switching
you from glWhateverEXT() to glWhatever() if there might be slight
behavior differences between the two that hadn't been identified. The
downside is that it means we can't share the resolver functions among aliases.