Added fallback extension for POSIX.
Use _uptime_posix in main module.
Ignore object files.
Added _uptime_posix to the docs.
Version bump.
Reorganised modules into single package.
Can't do binary distribution anymore.
Just catch all errors, actually.
Left a debug thing in by mistake.
Distutils are hard.
Packages as programs work differently.
Just ignore broken ctypes now.

With the POSIX fallback, it's now at least conceivable that locations with a
broken ctypes can still figure out uptime with our library, so let's let them
try.
Clean with greater vigour.