Changed Travis_Commit snippet length to 7

7 characters matches the github commit snippet length

Author: Nicholas Mathison

.travis.yml

@@ -4,7 +4,7 @@ rvm:
 install:
 - ant install-ivy -DfailIvy=false
 before_script:
-- export VERSION=${TRAVIS_TAG}.${TRAVIS_COMMIT:0:8}
+- export VERSION=${TRAVIS_TAG}.${TRAVIS_COMMIT:0:7}
 - ant run-tests
 script:
 - ant -Dcompile.no=y -Dversion=${VERSION}