Use handlers instead of plain old functions as the first parameter to toolbar actions.
Refactor code so that the Toolbar behavior is determined by an array of L.Handlers, given as part of the class definition (rather than as an argument) and each responsible for handling its own UI element in the toolbar (ToolbarIcon).
Update popup toolbar example to use handler-based toolbars.
Fix inexplicable stacking of ToolbarIcons caused by width of 25.999 (instead of 26) being coerced to 25 by parseInt.
Install local version of leaflet-draw to test modified version (see manleyjster/Leaflet.draw#toolbar-handler for the modified version).
Add child actions from ToolbarIcon.
Revert to earlier API - toolbars receive an array of toolbar actions (function which return a handler) as their first argument. Assume that each handler inherits from L.ToolbarHandler. Modify tests and examples to reflect new API.
Add L.Toolbar#appendToContainer method and refactor Toolbar and its subclasses to eliminate Toolbar#getContainer method and instead rely on a _container attribute.
Call Toolbar#addTo and Toolbar#appendToContainer from ToolbarIcon in order to add subToolbars to the map.
Update examples to match latest API and add sub-toolbar example.
Get rid of 'leaflet-toolbar' class and give each toolbar a depth-dependent class ('leaflet-toolbar-n' for a toolbar at depth n).  Style secondary toolbar for L.Toolbar.Control. Remove sub-toolbar when its parent action is disabled.
Add marker, rectangle, and circle handlers to Leaflet.draw example toolbars and fix issue with arguments passed to sub-toolbars.
Add tests for L.Toolbar#hide, #show, and #appendToContainer, and L.ToolbarIcon#onAdd.
Add tests for L.ToolbarIcon#_addSubToolbar with empty and nonempty sub-toolbars.
Remove test dependency on Leaflet.draw.
Move L.ToolbarHandler from Leaflet.draw back into Leaflet.Toolbar, move _addSubToolbar method from ToolbarIcon to ToolbarHandler, and fix tests accordingly.
Add tests for ToolbarHandler and Toolbar.
Add tooltips to toolbar examples (and add default tooltip option to ToolbarIcon).
Pull Leaflet.draw from forked repository on github.