Adds the gitinfo and the clean-gitinfo (last one used in build target) targets
Uses the new runtime/gitinfo.ftl in footers (all themes) like is the runtime/ftlinfo.ftl one
Actually both are shown (if you have a mix of repos, like I do) or one or the other
Adds the runtime/gitinfo.ftl file in both .gitignore and svn ignore

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1597615 13f79535-47bb-0310-9956-ffa450edef68