1) Commented out RESTEASY-903-AS7 and RESTEASY-903-WF8 in
arquillian/pom.xml; 2) Fixed package declaration in resteasy-jaxrs:
org/jboss/resteasy/test/providers/datasource/RESTEASY775Test.java.
RESTEASY-1106: ResponseBuilderImpl.links() removes previously added Link-Headers

This fixes the links()-implementation to reset the Link-headers only if
null is provided as argument - as specified in the Interface.

Simple test is included.
Merge pull request #569 from ja-fra/RESTEASY-1106

RESTEASY-1106: ResponseBuilderImpl.links() removes previously added Link-Headers
RESTEASY-1107
Merge pull request #570 from patriot1burke/master

RESTEASY-1107
setRequestUri fixes
Merge pull request #571 from patriot1burke/master

setRequestUri fixes
Merge branch 'master' of https://github.com/resteasy/Resteasy
RESTEASY-1103: Added XML security features to DocumentProvider.
Merge branch '1103'
RESTEASY-1103: Added constants to ResteasyContextParameters.
Merge branch '1103'
RESTEASY-1103: Updated docs.
Merge pull request #572 from ronsigal/master

RESTEASY-1103