Do not pass tile grid to getTile and tileUrlFunc

getTile and the tileUrlFunc are functions of the source, so they do need to be passed the tile grid. The tile source knows its tile grid, and can get the projection's tile grid if it doesn't have a tile grid.
Merge pull request #450 from elemoine/projection-null

Do not pass tile grid to getTile and tileUrlFunc
Update to latest version of pake
Merge pull request #455 from twpayne/update-pake

Update to latest version of pake
Hide the zoom buttons on print
Remove unused ol-renderer-webgl-canvas css class
Merge pull request #440 from fredj/css-print

css cleanups
Fix typo in example.
Rename *.exports to match their *.js counterparts.
Merge pull request #461 from marcjansen/istanbul

Fix typo in example.
More renames as suggested by @elemoine.
Merge pull request #462 from marcjansen/same-name

Rename *.exports to match their *.js counterparts.
Lowercase type in externs/bootstrap.js
Merge pull request #464 from fredj/externs-bootstrap

Lowercase type in externs/bootstrap.js
Add goog.base(this) to the MapBrowserEventHandler's constructor
Abort rendering when WebGL context is lost
Merge pull request #469 from twpayne/webgl-context-lost

Abort rendering when WebGL context is lost
Merge pull request #470 from szymonc/error-fix

Add goog.base(this) to the MapBrowserEventHandler's constructor