When configuring SIP URIs in the pjsip.conf file it is
necessary to escape the semicolon so the parser does not
treat it as a comment. This change allows this to work in
the astconfigparser implementation.

A secondary bug where some data was lost if a configuration
option included a "=" in its value was also fixed.

A bug where sections would be considered equal despite
being different has also been fixed.

Change-Id: If229f656ef22050b50e7b34e90c4bffe796431f8