Merge pull request #13 from geomajas/GJP-9-Zoom-to-selection

Gjp 9 zoom to selection
GJP-15: add and remove layer: new handlers and events
Merge pull request #14 from geomajas/GJP-15_addRemoveLayer

GJP-15: add and remove layer: new handlers and events
GJP-9 - Zoom to selection started
Implemented needed interfaces and classes.
temporary impl
Casted interface
add git ignore