start being able to be positioned relative to parent extent

* fixes #690
* I introduced the constraint of the value being smaller than 1
  because it should be rare for elements to be positioned outside
  of their parent container and if so not relative to it. I'm
  scared about cases where people do calculations ending up in
  floats and suddenly 100.3 is interpreted as 100 times the
  width of the parent. Would be weird.
Fix for letting Gradients through ColorFactory
Restrict relative values to be less or equal to 1
Streamline the if, thanks @jasonrclark
values can only be relative is there is a parent

* good thing I ran the specs once more, thanks expert-tankspank
Mark good-vjot as not working... see #255
Merge pull request #694 from PragTob/relative_position

start (left/top) being able to be positioned relative to parent extent
Changed email and author to team shoes

* steve is still there and supporting just not really active in
  development these days, I feel like "Team Shoes" represents
  us quite nicely :)
Add JRuby notice to gem description

* I did not find a way to specify an appropriate platform,
  there is 'java' but gems like warbler don't seem to do that
  and it might add -java to the gem name from what I
  gathered
Initial remodeling moving the Java/JRuby instructions up
More changes/fixups
Getting rid off the DevKit information for Windows

* I believe it is not needed as we are on Java?! cc: @ashbb
* At least for my windows installations I never needed it, as
  we are on Java a compiler etc. should be unnecessary and now
  with deactivated C-extensions support...
I am used to the bundler gem tasks :) specifically for release
Merge pull request #697 from shoes/readme_changes_for_release

README: Initial remodeling moving the Java/JRuby instructions up
Add a bit of information for Windows.
Merge pull request #693 from shoes/leaking_colors

Releasing Swt::Graphics::Color resources
Merge branch 'master' into leak_hunter_keypress