version bump and readme update

Merge branch 'master' of github.com:gdsestimating/three-dxf

Fixed flipped min y and max y in extents coords

- Also updated sample bower.json dependency

Updated Three-dxf to work with Three.js r80

- Text works differently now. Must load a font and pass it to the ThreeDxf.Viewer constructor, and three.js now includes the font and text utilities
- Included font in sample directory instead of getting it from github
- Major Version bump for breaking changes

Missed bower version in last commit

merge

Added missing bower dependency to sample