2.0.0

Added

• new 'USATopo' L.esri.basemapLayer option.
• boilerplate issue template

Fixed

• Worked around IE10,11 bug that caused L.esri.featureLayers not to draw #770
• Ensured L.esri.imageMapLayer are overlaid appropriately at world scale #774
• Ensured copyright text makes it into the minified, concatenated build of the library
• create script tag after JSONP callback function is defined #762