[#569] Fix debug drawing for me.Line objects
Fix enemy collisions in platformer

- onCollision MUST now return false for "no response"; return undefined is not enough
- See: https://github.com/melonjs/melonJS/commit/41540435262c23c17705418046c943fac7712480
[#569] Convert all platform shapes in Platformer example to PolyLines

- This demonstrates a bug with setting the inViewport flag on me.Line, which may potentially have its height OR width === 0.
[#569] Fix the disappearing platforms

- Affects world entities created with TMX polygon/polyline (neither entity is given a width or height)
- Fix is to check inViewport using the entity bounds instead of the entity geometry
- It's still unclear if we want to keep the bounding box separate from the entity (which is already a rect)
[#569] Optimize me.Line and collision checks.

- 90% of me.Line was removed! Now inherits from me.Polygon
- Small optimizations in collision checks, especially me.collision.testPolygonPolygon no longer needs to compare the normals on a me.Line twice
Remove bower from the npm `install` command
[#569] Add support for initializing `me.Body` with a default list of shapes

- Makes `me.TMXObject.getShape` a private method, renames it to `getTMXShapes`, and returns an array
- `me.Entity` now initializes its body with a list of shapes using the private `settings.getTMXShapes` method
Fix exception when calling `me.Entity.body.updateBounds()` and the body has no shapes.
Fix the silly container example
Add collision boundaries to platformer example
[#542] Add tile animations to platformer TMX

- In preparation for animated tiles support in Tiled 0.10
updated README
also remove `flipX/flipY` from `me.Rect`, as once again it cannot be used anyway for collision
added the missing `containsPoint()` function to `me.Line`
[#540] added a rotate function to `me.Polygon`
fixed the "shapes" example
[#542] read the `rotation` property out of the TMX file

it is not yet apply for now, as shapes rotation related functions need
some more love before (rotate `me.Polygon` around its center point by
default, and add a rotation function to `me.Ellipse`)
fixed trailing whitespace
[#52] added a basic isometric example to test the new shape based Tile collision system

based on the following one, courtesy of Pierre, that I had hanging
around since a while :
https://github.com/mfpierre/melonJS/tree/isometric_example
forgot to remove this one !