Ability to add buildaction in response to https://issues.jenkins-ci.org/browse/JENKINS-20577

This allows a user to enter a specific buildaction like test or analyze . The JIRA is here: https://issues.jenkins-ci.org/browse/JENKINS-20577

Previously, the only buildaction supported was to build.  This change allows a user to specify a different buildaction like "test".  The various build actions are specified by Apple here: https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/xcodebuild.1.html

![screen shot 2013-11-14 at 2 54 41 pm](https://f.cloud.github.com/assets/376307/1546100/e4b2ed0a-4d7f-11e3-8b70-ec3371265055.png)