Add Florian Forster to hall of fame

Permission recieved from Florian Forster on Jan 07 2013 to include
any changes of his from core Git into LibGit2.
Revert changes from git/git diff-delta.c by dak@gnu.org, proski@gnu.org
Merge pull request #1202 from martinwoodward/add-florian

Add Florian Forster to hall of fame
Merge pull request #1203 from phkelley/reverse_dak

Revert changes from git/git diff-delta.c by dak@gnu.org, proski@gnu.org
Introduce git_diff_blob_to_buffer
Share git_diff_blobs/git_diff_blob_to_buffer code

This moves the implementation of these two APIs into common code
that will be shared between the two.  Also, this adds tests for
the `git_diff_blob_to_buffer` API.  Lastly, this adds some extra
`const` to a few places that can use it.
Merge pull request #1204 from arrbee/diff-blob-to-buffer

Have diff blob to buffer share code (and add tests)
keep comments at < 80 chars
Merge pull request #1207 from ethomson/cmake_comment_len_sanity

keep comments at < 80 chars
remove ppc sha1 asm
Merge pull request #1208 from ethomson/ppc_sha1_asm_deadness

remove ppc sha1 asm
update copyrights
Merge pull request #1209 from ethomson/update_copyright

update copyrights
Resolve crash with diff against empty file

It is not legal inside our `p_mmap` function to mmap a zero length
file.  This adds a test that exercises that case inside diff and
fixes the code path where we would try to do that.

The fix turns out not to be a lot of code since our default file
content is already initialized to "" which works in this case.

Fixes #1210
Merge pull request #1212 from arrbee/fix-diff-empty-file

Resolve crash with diff against empty file
Relax refspecs accepted by push
tests-clar/network: remove unused CREATE_BLOB
push: properly handle tags

Currently, push doesn't really handle tags when queueing objects. Fix
it.
Merge pull request #1214 from schu/push-handle-tags

push: properly handle tags
Add a failing test for autocrlf filters