begin with the correct 2 bytes.

With both the `curl` api command and application, you can now ask for
data to be PUT where previously it could only be sent via POST.

Merge pull request #2 in FS/freeswitch from ~KATHLEEN.KING/freeswitch-fork:doxygen-switch_apr.h to master

* commit '64fc3f79':
  Changed the function parameter name in the function definition to match the updated parameter name in the function declaration. #doxygen
  Changed the variable name for clarity.

match the updated parameter name in the function declaration. #doxygen

Merge pull request #4 in FS/freeswitch from ~KATHLEEN.KING/freeswitch-fork:doxygen-switch_regex.h-2 to master

* commit '35755d37':
  Fixed parameter name of variable in switch_regex_match_partial. #doxygen

* commit 'b0e86e65':
  misc of python pep8 fixes

switch_regex_match_partial. #doxygen

Set the algorithm member on cipher_t when allocating AES crypto instance.  Apply same fix to NULL cipher.

In `srtp_unprotect_rtcp()` we are not validating that the packet
length is as long as the minimum required.  This would cause
`enc_octet_len` to underflow, which would cause us to try to decrypt
data past the end of the packet in memory -- a buffer over-read and
buffer overflow.

In `srtp_protect_rtcp()`, we were similarly not validating the packet
length.  Here we were also polluting the address of the SRTCP
encrypted flag and index (the `trailer`), causing us to write one word
to a bogus memory address before getting to the encryption where we
would also overflow.

In this commit we add checks to appropriately validate the RTCP/SRTCP
packet lengths.

`srtp_unprotect_rtcp_aead()` (but not protect) did correctly validate
the packet length; this check would now be redundant as the check in
`srtcp_unprotect_rtcp()` will also run first, so it has been removed.

In the defined AEAD modes, SRTP packets must always be encrypted and
authenticated, but SRTCP packets may be only authenticated.  It's
possible, therefore, for us to end up in `srtp_protect_aead()` without
the `sec_serv_conf` bit being set.  We should just ignore this and
encrypt the RTP packet anyway.

What we are doing instead is encrypting the packet anyway, but setting
`enc_start` to NULL first.  This causes `aad_len` to underflow which
will cause us to over-read in `cipher_set_aad()`.

If we could get past that, we would try to read and write memory
starting at 0x0 down in `cipher_encrypt()`.

This commit causes us to not check the `sec_serv_conf` bit and never
set `enc_start` to NULL in `srtp_protect_aead()`.

`srtp_unprotect_aead()` does not contain a similar error.