Removed TextSerialization support--meaningless and not used.
Changed call to getRawHeader() to getHeader() in getFormat().
Removed Text serialization
Intermediate check-in re. content-type negotiation.  3 tests fail.
Merge branch 'master' into content-type-negotiation
Merge branch 'master' into content-type-negotiation

Conflicts:
	core/src/java/com/strategicgains/restexpress/RestExpress.java
	core/src/java/com/strategicgains/restexpress/response/ResponseProcessor.java
	core/src/java/com/strategicgains/restexpress/serialization/text/DefaultTxtProcessor.java
	core/src/java/com/strategicgains/restexpress/serialization/text/TextSerializer.java
	core/test/java/com/strategicgains/restexpress/RestExpressTest.java
Refactoring toward SerializationProvider. Intermediate check-in--tests not passing yet.
Continued refactoring toward SerializationProvider supporting content-type negotiation.  Intermediate check-in.
Intermediate check-in. Still refactoring towards SerializationProvider with content-type negotiation for both request/response.
Merge branch 'master' into content-type-negotiation. Tests run: 285, Failures: 12, Errors: 3, Skipped: 0

Conflicts:
	core/src/java/com/strategicgains/restexpress/RestExpress.java
Intermediate checkin: Tests run: 285, Failures: 7, Errors: 0, Skipped: 0
Content-Type Negotiation: Tests run: 285, Failures: 0, Errors: 0, Skipped: 0
Fixed issue where 406 status should be returned for unsupported/invalid media type requested.
Removed ResponseProcessorResolver as the functionality is now in SerializationProvider.
Added early resolution for Response media type to enable 406 (Not Acceptable) without incurring the expense (and possibly erroneous headers and such) of performing the whole cycle before returning 406.