a bunch of cleanup for latest
Merge pull request #127 from kevmoo/patch-4

a bunch of cleanup for latest
Get rid of warning in Dart2Js

"Warning: Unreachable code"
Merge pull request #128 from Fox32/patch-1

Get rid of warning in Dart2Js
Set version constraints to any for now

We should consider setting them in the future!
Merge pull request #130 from Fox32/patch-1

Set version constraints to any for now
Add addVector to debug draw manager to draw a vector at origin (in form of an arrow)
Merge pull request #131 from Fox32/feature/debug-draw-manager-add-vector

Add addVector to debug draw manager
Allow as many vertex buffers in parallel as the device supports
Fix #132
Merge pull request #133 from Fox32/vbo-count

Allow as many vertex buffers in parallel as the device supports
DebugDrawManager: Don't upload or draw anything if there is nothing to draw
Merge pull request #134 from Fox32/improve-debug-draw-manager-performance

DebugDrawManager: Don't upload or draw anything if there is nothing to draw