+ Added preliminary support for HTTP authentication using same
  credentials as for traditional RT REST (user= & pass=)
* Correctly handle 'No matching results' response from REST endpoint,
  existing code throws NPE (stack trace cropped for readability):
  java.lang.NullPointerException
   at java.util.regex.Matcher.getTextLength(Matcher.java:1140)
   at java.util.regex.Matcher.reset(Matcher.java:291)
   at java.util.regex.Matcher.<init>(Matcher.java:211)
   at java.util.regex.Pattern.matcher(Pattern.java:888)
   at de.boksa.rt.rest.response.parser.processor.FieldProcessorRegistry.getTicketFieldProcessor(FieldProcessorRegistry.java:59)
   at de.boksa.rt.rest.response.parser.MultilineTicketSearchResponseParser.processTicketData(MultilineTicketSearchResponseParser.java:97)
   at de.boksa.rt.rest.response.parser.MultilineTicketSearchResponseParser.processResultData(MultilineTicketSearchResponseParser.java:85)
   at de.boksa.rt.rest.response.parser.MultilineTicketSearchResponseParser.parseTicketSearchResponse(MultilineTicketSearchResponseParser.java:78)
   at de.boksa.rt.dao.RESTRTTicketDAO.findByQuery(RESTRTTicketDAO.java:72)
   at de.boksa.rt.dao.RESTRTTicketDAO.findByQuery(RESTRTTicketDAO.java:54)
   ...
+ RTTicket now exposes the full set of ticket fields
- Removed useless statement (System.out.println) left of debugging
* Allocate HTTP context when instantiating RTRESTClient to allow
  authentication credentials to be cached
Added some new models and functionality, including a function to get an RT user