Support starting the maven build from a directory distinct from rhq root

Why: because maven's parent shell's pwd is not always under our control. I have seen this happening in Jenkins or when I build using a shell script started as Eclipse's external tool.
On Thursday, September 04, 2014 12:49:22 PM Peter Palaga wrote:
> 
> Yes, as already mentioned on IRC, this is a build script, for which only the
> java used to run maven is important. @burmanm said this is OK, as the RHQ
> source level is probably at Java 7 anyway. You mean that @burmanm is not
> right?
> 

No I wrote that comment without actually checking what the file does and where 
it is used. Seeing it did something with storage node I assumed it was part of 
the installer and thus the Java6 rule applied to it. Mea culpa.

> It is true that RHQ target level is at Java 6, but that is fully
> reconcilable with this build script using Java 7.
>

Yes, build *requires* Java7 even though the resulting binaries are Java6. If 
this is a build time script, and I trust you and @burmanm that it is (still 
too lazy to check ;) ), then you are right. Java7 APIs should be OK there.

> ---
> Reply to this email directly or view it on GitHub:
> https://github.com/rhq-project/rhq/pull/119/files#r17137537