removed refset from hpack
update encoding strategy for no ref-set
do not index content-length
Merge branch 'jetty-http2' into refset

Conflicts:
	jetty-http2/http2-hpack/src/test/java/org/eclipse/jetty/http2/hpack/HpackEncoderTest.java
updates for hpack huffman and examples
Merge branch 'jetty-http2' into refset
Updates to hpack for hpack-09 draft