Adds a standard typesafe-config reference.conf file that sets c3p0
config to prevents Tomcat memory leaks on hot-redeploy/shutdown.

See
   http://www.mchange.com/projects/c3p0/#configuring_to_avoid_memory_leaks_on_redeploy
   http://www.mchange.com/projects/c3p0/#tomcat-specific

This new config can be overridden in an application.conf or
c3p0.properties file.

( See http://www.mchange.com/projects/c3p0/#configuration_precedence )

Updates c3p0 version to c3p0-0.9.5.2, which fixes that leads to
unnecessary String allocation when logging via slf4j.