TS-2316: header_rewrite: unify style

Submitted by: Alexey Ivanov <aivanov@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: removed trailing spaces

Submitted by: Alexey Ivanov <aivanov@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: fixed segfaults in ConditionPath::append_value()

Submitted by: Manjesh Nilange <mnilange@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: added variable expansion support to add-header

Submitted by: Thomas Jackson <thjackso@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: fix for crash in client header condition

Submitted by: Manjesh Nilange <mnilange@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: added optional counter to each rule

Now you can count each rule's tripping by providing one or more "counter"
statements e.g::

    cond %{SEND_RESPONSE_HDR_HOOK} [AND]
    add-header X-DC "DC1"
    counter plugins.header_rewrite.POP
    counter plugins.header_rewrite.ALL

Submitted by: Alexey Ivanov <aivanov@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: added cookie-based conditions

Submitted by: Alexey Ivanov <aivanov@linkedin.com>
Sponsored by: LinkedIn
TS-2316: header_rewrite: improved documentation

Added variable expansion, counter operation and cookie condition.
Removed non-existient METHOD condition example.

Submitted by: Alexey Ivanov <aivanov@linkedin.com>
Sponsored by: LinkedIn
TS-2339 Cleanup Makefile.am, fix wrong _SOURCES definitions
Added TS-2339.
Merge branch 'master' of https://github.com/SaveTheRbtz/trafficserver
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/trafficserver
TS-2333 Change the SAX callbacks to not clash with libxml2
TS-2333 Use the right SAX.h include
TS-2338 Remove IPRange.cc and .h, and SocksParser.cc
Added TS-2338.
TS-2338 Remove IPRange.h from _SOURCES.