Set up the version on tag for maven

Author: doradito

Diff for: .travis.yml

@@ -1,6 +1,7 @@
 language: java
+install: true
 script:
-  - mvn install
+  - bash build.sh
 env:
   global:
   - secure: g0A9usPhe/Tj0lnuCwUHgA88fsJ0eU1sgBCUUEUXDSE9wqyHs8ossEagRXOv3RFA+mULCXHuiSyD0CCkvfSfvL9zYzZO3XOcNiMy8GWZahUtYJph256bvw8D5/Y+HJTD8ppvPYjptKs6RyQSfQw796XIMUWHQQhUaKX6a2jho40=

Diff for: build.sh

@@ -0,0 +1,7 @@
+set -e
+
+if [ ! -z "${TRAVIS_TAG:-}" ]; then
+  mvn versions:set -DnewVersion="${TRAVIS_TAG#v}"
+fi
+
+mvn install