Multiple executions of Maven goal "prepare-agent" should not lead to
incorrect configuration (GitHub #40).
Also consider quotes in command line arguments correctly.

For this move command line utilities into core.
Merge pull request #146 from jacoco/issue-146

Rebased fix for issue #40 (doubled javaagent)
Avoid direct dependency on java.lang.management APIs to allow usage on
Android (GitHub #150).
Add TeamCity to integration matrix.