Added Gitter badge
Merge pull request #6 from gitter-badger/gitter-badge

Add a Gitter chat badge to README.md
Fixing build.xml:
Fixed time stamp.
Added Class-Path to manifest.
Added Main-Class to manifest.
Removed invalid exclude.
Minor cleanup.
Fixing minor typo from
L2J/L2J_Server@ac426d90c3f02bb4f1916f1d23314c365c306907 preventing
multisells and other bypasses to be properly formed (NPC Object ID) fron
onTalk().