Rename 'eap-6_1' assembly to 'eap6_3'

 * the 6_1 is leftover from 6.0.x, where the
   taget was EAP 6.1. However, for KIE 6.2.0
   the target is EAP 6.3.
Merge pull request #21 from psiroky/rename-eap-assembly

Rename 'eap-6_1' assembly to 'eap6_3'