Update drawing feature

[dcdenu4]

This PR stabilizes the drawing polygon feature. It provides updated styling:

• dotted lines on draw, solid on completion
• polygon button stays darker grey when in draw mode
• polygon button and trash button have more useful tooltip information

Wording has been updated for the "local" scale option and its info popup.

This PR also fixes bug #121 . Making sure that there are valid returned features before highlighting.

This PR also tackles #120 . Adding gadm1 support files to use as filters and local geocoders to only return results from searching that match gadm1.

Fixes #10 Fixes #121 Fixes #120