Identify

This adds most features of the Identify Tool plugin to the main Identify map tool

please add your comments/suggestions

a tab widget allows to see the data in one of 3 ways

- Tree, as previously
- Table, a table view of Vector and Raster layers (Layer, FID, Attribute, Value)
- Graph which shows a plot of raster layers, very basic for now (virtually identical to the plugin) and only qwt5 for now