factored out servlet utility classes/methods

This will allow them to be used by multiple projects.
change repo webapp to use web service util library
add c3p0 libs to repoapp WEB-INF/lib
add header comment, javadoc
fix default builder web service ctx path

Also, added config properties for builder web service
client username and password.  (For now, only one
client is assumed to exist.)
added doPost in BWS Submit servlet

Doesn't do much yet - just parses a JSON object out of the request.
extract field values from request data