Refactor: Use STL functions to parse isasl.pw
Refactor: Use STL functions to parse isasl.pw

Replace our own functions to tokenize the line with STL
methods and just inline one-liner-functions.

This is a preparation for adding support for the new format
for the SASL user database.

Change-Id: Ia245063b3c8d5ca3bfe838f00b761fa9ee408575
Reviewed-on: http://review.couchbase.org/58255
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

owendCB/memcached,daverigby/memcached,daverigby/kv_engine,daverigby/kv_engine,owendCB/memcached,couchbase/memcached,owendCB/memcached,owendCB/memcached,couchbase/memcached,daverigby/memcached,daverigby/memcached,daverigby/kv_engine,couchbase/memcached,couchbase/memcached,daverigby/memcached,daverigby/kv_engine