Smack: do not use snapshots

Upgrade to latest Smack API and client-common-java

Signed-off-by: Daniele Ricci <daniele.athome@gmail.com>
Merge branch 'master' into ptt_message

Signed-off-by: Andrea Cappelli <a.cappelli87@gmail.com>

Conflicts:
	app/build.gradle
Merge branch 'ptt_message' into progress_balloon
Merge branch 'progress_balloon' of https://github.com/kontalk/androidclient into progress_balloon