Fixed memory leak
Added tags to .gitignore

This file is generated by ctags.
auth: removed useless static declaration

_handle_open_tls() declared as static function but not defined.
sasl: don't use uninitialized variable

base64_decode() used uninitialized variable when unable to allocate memory.

Reported-by: Fabian Freyer <fabian.freyer@physik.tu-berlin.de>
SCRAM-SHA-1 authentication mechanism support
md5: MD5Transform should be static
sha1: workaround for name collision with libcrypto

src/sha1.c is used only for internal purposes. So, just add prefix
xmpp_ to the SHA1 symbols.
Merge remote-tracking branch 'upstream/master'