add preemptive basic auth

Conflicts:
	src/main/java/org/jboss/aerogear/unifiedpush/async/AsyncClient.java
	src/main/java/org/jboss/aerogear/unifiedpush/resteasy/RestEasyClient.java
	src/test/java/org/jboss/aerogear/unifiedpush/DefaultJavaSenderTest.java
Merge branch 'AGPUSH-97'
Preparing to release 0.1.0