#54: Reveal describe details (tag name, number of commits)

[TheSnoozer]

Hi @ktoso,
today I had some time to implement the feature for #54.
This PR looks huge but it isn't.
Most what I did was shifting code from DescribeCommand.java to a new class JGitCommon.java to make it easier accessible. This basically gave me the opportunity to reuse the major part of the functionality. We still could speed up the JGit-Implementation by saving the values we need twice but I leave this as optional :-9

Also I fixed the license-headers (some files had a duplicated license info) and added the new properties to the readme (I caught one that was missing...).

Let me know if I should improve something for the PR.

Thanks,

[ktoso]

Sounds great, reviewing!

[ktoso]

Let's remove all @author tags by the way, to make nier to feel collective ownership about the code. I'll do that. :-)

[TheSnoozer]

Well I think we could make it static.
In one of my projects I learned the hard way to avoid static method calls and rather go for new Clazz().method ;-)
I think this memory is burned into my head :-)

[ktoso]

Or better just pass the instance around ;)

[TheSnoozer]

Mhh I think I would leave it as it is right now :-)
Passing only a single instance around or making the calls static is something I would leave optional for further improvement :-P

[ktoso]

Though I would much rather have it passed in from the "beginning of the control flow" (the plugin, or the test) let's go with the current impl for now ;-)

[ktoso]

Thanks, merged!