Added support for GeoJSON objects in polygon & polyline directives

* Added support for GeoJSON objects in the polygon & polyline directives.  The path attribute/parameter can now be set with either the existing latitude/longitude object arrays or a GeoJSON Polygon or LineString object.

* Added example page using GeoJSON coordinates in the polygon/polyline directives. (example/geojson.html)

* Added static parameter/attribute to polyline directive to make it similar to the polygon directive.  (Setting the static attribute to true implies that the polyline's points are static (do not change). The performance benefit comes from the fact that the directive does not need to perform deep watch on every polyline co-ordinate for every Angular digest cycle.

* Added example page with polygons containing a huge number of points to demonstrate the use of the new static parameter/attribute. (example/hugedata.html).

##### Documentation
A seperate pull request will be submitted against the website branch to update the documentation for these directives

##### Discussion
At this time, I've decided against adding support for GeoJSON objects to the google-maps, marker, window, circle and rectangle directives. I would be willing to add support if there is demand.