v0.3.0

Add support of css class per item group.

Change format for specyfying buttons (breaking).

v0.2.2

Add support of css class per item group

THIS IS A BREAKING CHANGE.

v0.2.1

Allow to divide buttons into visual groups.

v0.2.0

Split condition into visible and enabled conditions.

v0.1.2

Fixes the issue with dispatching digest cycle too often on zoom & pan events.

v0.1.1: Run digest cycle on graph's zoom and pan events

Rationale: we want to add "fit" and "zoom to central object" buttons
that should be visible when graph is not fitted or is not zoomed to
the center respectively. It's simple to write such conditions for
buttons but they need to be recalculated as the graph is zoomed or
panned.

Angularized version of plugin

v0.1.0

Add container for bs-tooltip