Movement Updates (#2247)

This is a squash and merge of a large set of changes by @BeksOmega 

* Added functionality to scrolling, dragging, and zooming.

* Fixed incorrect changes to workspaceChanged function.

* Fixed comment.

* Fixed typo.

* Removed scrollbar.set calls from workspace_svg.

* Removed scrollbar.resize() call.

* Added move options to playground.

* Fixed scroll_ calls that replaced scrollbar.set calls.

* Removed this.scrollbar checks.

* Changed zoom so that it always zooms towards the coordinates. Changed isContentBounded_ to be separate from isMovable_ (b/c of the previous change zoomControls had to be added to the bounded check). Fixed scroll_() calls... again.

* Changed procedures so the Highlight definition option is only available if the workspace is moveable.

* Fixed scrollCenter so that it works with flyout toolboxes.

* Fixed zoomToFit so that it works with horizontal flyout toolboxes.

* Fixed Typo.

* Fixed bumping blocks when the workspace is not movable.

* Fixed bumping not working with left and top toolbox positions.

* Re-Added not allowing scrollCenter if the workspace is not movable. Disabled scrollCenter button for this case.

* Cleaned up formatting.

* Fixed bumping... again. Reformatted workspaceChanged a bit.

* Changed blocks to be completely bumped into the workspace.

* Reorganized metrics-getting for workspaceChanged.

* Added bumping workspace comments. Moved event checking.

* Renamed workspaceChanged to bumpObjects.

* Added a bumpObjects developer reminder.

* Added warning to zoomToFit.

* Cleaned up some text.

* Added better inline documentation.

* Fixed up inline docs.

* Cleaned up comments.

* Fixed zoomCenter not actually zooming towards the center.

* Fixed zoomControls error on unmovable bottom-toolbox workspaces

* Fixed programatically placing blocks in an unmovable workspace.

* Removed unnecessary translate call in inject.

* Reversed removal of translate. (apparently it was necessary)

* Cleaned up code in response to first round of reviews.

* Added unit comments to the zoom function.

* Removed bumpObjectsEventChecker. Added BUMP_EVENTS list to Blockly.Events.

* Changed getWorkspaceObjectMetrics call to getBoundingRectangle().

* Fixed utils.mouseToSvg (was causing problems with zoom on wheel if the page was scrolled).

* Fixed zoom when page is scrolled (actually this time). Reverted changes to utils.mouseToSvg.

* Fixed centerOnBlock.

* Added unit docs to translate. Moved setting the grid position to the translate function.

* Added TODO's.

blocks/procedures.js

@@ -948,6 +948,12 @@ Blockly.Blocks['procedures_callnoreturn'] = {
    * @this Blockly.Block
    */
   customContextMenu: function(options) {
+    if (!this.workspace.isMovable()) {
+      // If we center on the block and the workspace isn't movable we could
+      // loose blocks at the edges of the workspace.
+      return;
+    }
+
     var option = {enabled: true};
     option.text = Blockly.Msg['PROCEDURES_HIGHLIGHT_DEF'];
     var name = this.getProcedureCall();