Updated session expiration

Added interval to the proxy lib that terminates client connections
when the session expiration has been passed. Added config file
option to specify the interval time. Added session attribute
"lastAction" to determine the session renewal grace period.
Changed session "expireAt" attribute to use a future date with a
TTL of 0. Added IDEA project files to gitignore.
Added configuration defaults and error checking

Added JSV and jsvutil Node packages.
Created JSON schema for config file.
Changed proxy to validate config file using jsvutil.
Changed proxy and sub-modules to use config generated by jsvutil.
Added TLS key and certificate validation to proxy.
All validation generates appropriate error messages.