core: Make explicit version of maven ear plugin
core: Make explicit version of maven ear plugin

Currently we don't explicitly specify the version of the maven ear
plugin that we use. This patch makes it explicit in the plugin
management section of the root POM.

Change-Id: Icf66612379bb1b9506b617771a8ee32c6491931a
Signed-off-by: Juan Hernandez <59e5b8140de97cc91c3fb6c5342dce948469af8c@redhat.com>

walteryang47/ovirt-engine,yapengsong/ovirt-engine,walteryang47/ovirt-engine,OpenUniversity/ovirt-engine,yingyun001/ovirt-engine,OpenUniversity/ovirt-engine,zerodengxinchao/ovirt-engine,OpenUniversity/ovirt-engine,eayun/ovirt-engine,halober/ovirt-engine,yapengsong/ovirt-engine,yingyun001/ovirt-engine,zerodengxinchao/ovirt-engine,zerodengxinchao/ovirt-engine,zerodengxinchao/ovirt-engine,yingyun001/ovirt-engine,OpenUniversity/ovirt-engine,eayun/ovirt-engine,halober/ovirt-engine,yapengsong/ovirt-engine,OpenUniversity/ovirt-engine,walteryang47/ovirt-engine,walteryang47/ovirt-engine,eayun/ovirt-engine,yingyun001/ovirt-engine,yapengsong/ovirt-engine,halober/ovirt-engine,walteryang47/ovirt-engine,eayun/ovirt-engine,yingyun001/ovirt-engine,eayun/ovirt-engine,zerodengxinchao/ovirt-engine,halober/ovirt-engine,yapengsong/ovirt-engine