[JENKINS-22820] fix - Bump maven.scm to 1.9.1 to avoid issues with Git v1.9 upgrades.

The v1.9.1 version changes to use --porcelain mode, which prevents the parsing bug.

maven-release-plugin needs to be bumped to 2.5 since it has a dependency on maven-scm-api 1.9.

![image](https://cloud.githubusercontent.com/assets/326857/4018640/745de06e-2a51-11e4-917e-ca245ceabf68.png)

components.xml had to be updated to support Git-related tests too.

https://issues.jenkins-ci.org/browse/JENKINS-22820

Relates to: https://jira.codehaus.org/browse/SCM-686