Completed first pass of road digitizer tool

Added new tool to makefile and fixed some issues

fixed some references crashes

re-organized road

made changes since snapping does not work for background layers

moving from QgsPoints to plain floats to make basic functions work

working example of more than one pair of segments

comparison of floats more safe with abs

replaced 1e-7 with 1e-4

Added new median function for road digitizer
Completed second pass of road digitizer tool

new polyline function added

Moved from segments to vertices to control the order of the selected nodes

Re-applying the algorithm with extra points
Added documentation for the new tool and updated plugin metadata
Renamed DigitizeRoad to DigitizeMedianLine

Disable debugging prints

Removed double Qt imports (#9)

Renamed files (#9)

Renamed icons (#9)

Renamed DigitizeRoad to DigitizeMedianLine (#9)
Merge pull request #10 from kalxas/roads

Added tool to digitize median line between adjucent polygons