This converts blob.c, fileops.c, and all of the win32 files.
Also, various minor cleanups throughout the code. Plus, in
testing the win32 build, I cleaned up a bunch (although not
all) of the warnings with the 64-bit build.
See `global.c` for a description of what we're doing.
When libgit2 is built with GIT_THREADS support, the threading system
must be explicitly initialized with `git_threads_init()`.
1. The license header is technically not valid if it doesn't have a
copyright signature.
2. The COPYING file has been updated with the different licenses used in
the project.
3. The full GPLv2 header in each file annoys me.
This code is useful for more things than just the packfile handling
code. Factor it out so it can be reused.
Signed-off-by: Carlos Martín Nieto <carlos@cmartin.tk>