Add Apache license header back to libpqueue files

The original libpqueue file were licensed under Apache 2.0 so
therefore should retain their copyrights and header as per the
license terms at http://www.apache.org/licenses/LICENSE-2.0
Fix bug in gen_pktline() for deletes of missing remote refs

* gen_pktline() in smart_protocol.c was skipping refspecs that deleted
  refs that were not advertised by the server.  The new behavior is to
  send a delete command with an old-id of zero, which matches the behavior
  of the official git client.
* Update test_network_push__delete() in reaction to above fix.
* Obviate messy logic that handles missing push_spec rrefs by canonicalizing
  push_spec.  After calculate_work(), loid, roid, and rref, are filled in with
  exactly what is sent to the server
Add full license notice to bsearch code

The original BSD glibc code contains the notice as given at
http://opensource.apple.com/source/gcc/gcc-5666.3/libiberty/bsearch.c
and should be given in full along with the code.
Give proper license notice to code from Android

The usage of the Android derrived code contains a full notice
which must be provided with the source code as per the terms
given at:
https://android.googlesource.com/platform/bionic/+/android-4.0.3_r1.1/libc/bionic/dirname_r.c
MERGE_HEAD contents iterator
Merge pull request #1186 from martinwoodward/compliance-audit

License Compliance Audit
Add Brian Downing to the hall of fame
Merge pull request #1187 from martinwoodward/give-props

Add Brian Downing to the hall of fame
Add note in CONVENTIONS about inlined functions
Remove whitespace
Merge pull request #1188 from tnm/inline-convention

Inline convention
Merge pull request #1183 from congyiwu/push_delete_fix

Fix bug in gen_pktline() for deletes of missing remote refs
Merge pull request #1184 from ethomson/mergehead_iterator

MERGE_HEAD contents iterator