Removes and embedded assignation for readability purposes.

https://github.com/alobbs/libhpack/commit/af00166bb154f814bd6bf9e2267c49b7ceee006c
Covers corner case in cherokee_buffer_move_to_begin

cherokee_buffer_move_to_begin did not cover the case when 'pos'
is equal to zero. It did not crash, although it was doing work
for nothing.

https://github.com/alobbs/libhpack/commit/fea7abd08560052a24fda45a0821ec2e70f551fa
Fixes cherokee_buffer_remove_string() corner cases

The cases where cherokee_buffer_remove_string() received either a
NULL string to search for, or one empty were not properly handled.

https://github.com/alobbs/libhpack/commit/66b0c00321fc9f624efd667b7e40e0c485751992
cherokee_buffer_remove_chunk() corner cases coverage

Some of the corner cases of cherokee_buffer_remove_chunk() weren't
covered properly.

https://github.com/alobbs/libhpack/commit/a4500486bf1acca0fc10f9c7c6db39a13fc27b71
cherokee_buffer_crc32() did not handle empty buffers correctly.

https://github.com/alobbs/libhpack/commit/8ae40a4f406743243c9dddc5a3588d5ee58a333f
Memory management improvement in cherokee_buffer_read_file

Allocate the memory to read a file into the buffer only after the file
has actually been opened successfully. Previously, the buffer was
grown before the file was open, so if it failed, the buffer was
remained enlarged.

https://github.com/alobbs/libhpack/commit/50dc464eca5ec762cdceac7c04ee3eb07dca081a
Adds a sanity check in cherokee_buffer_read_from_fd

Adds a new sanity check in cherokee_buffer_read_from_fd()
to make sure the fd provided is actually valid.

https://github.com/alobbs/libhpack/commit/8cc53d7bb796684707b8ad8d7d8063804a793a84#diff-b4eebe0e5503a49dd7a2a066b8e5114dR1195
Bug fix cherokee_buffer_multiply

It wasn't actually multiplying the content of the buffer by the
right number but the number plus one.

https://github.com/alobbs/libhpack/commit/4e804ee1aa895b12fe23a946adb58848cb5f96f9
Merge pull request #1074 from cherokee/libchula_buffer_fixes

Libchula buffer.c fixes