remove the 'isActive' test when merging simulation islands for constraints and speculative contacts, it is wrong
This fixes issue 709

git-svn-id: http://bullet.googlecode.com/svn/trunk@2670 08e121b0-ae19-0410-a57b-3be3395fd4fd
added two methods to btQuaternion, and add a note that the 'angle' method returns the half angle.
angleShortestPath and getAngleShortestPath
Thanks to Tully Foote. This fixes issue 379.


git-svn-id: http://bullet.googlecode.com/svn/trunk@2671 08e121b0-ae19-0410-a57b-3be3395fd4fd
prettify the debug wireframe drawing of sphere, capsule, cylinder and cone
add an btAssert in normalize of btVector3 and 'normalized' always use 'normalize'

git-svn-id: http://bullet.googlecode.com/svn/trunk@2672 08e121b0-ae19-0410-a57b-3be3395fd4fd