(bug) Fix parent destroy listener 'this' binding

The $destroy listener used -> which did not correctly bind @layer, 'this' came into the callback function as the window object. Therefore, an undefined reference was being thrown. Change -> to => so coffee will bind to _this.layer instead.
Merge pull request #317 from mikepugh/patch-1

(bug) Fix parent destroy listener 'this' binding
polyline, push a point onto existing polyline array no longer causes
infinite digest

- problem was we were changing scope which hit an event listener on the
  line itself from the Google Perspective which then remodified the path
from the scope perspective.. forever..

- fix was to add a boolean trip to make sure where the change is coming
  from to bail out, issue #301
version bump
Markers are now able to call a click function of the
controller...$markerModel will be injected

Small cleanups

example using  not console

rebased against 1.0.17
bumped to 1.0.18
Merge branch 'master' into pr334-negative-anchor-offsets

Conflicts:
	dist/angular-google-maps.js
	dist/angular-google-maps.min.js
Fixing bug where anchor values with zeros get ignored.
Marker label anchors can now be negative numbers as well. Updating spec to expect numbers for marker-label anchor instead of strings.