NET Elevations

[nawagers]

Elevations are currently being processed using 2D distance and aren't corrected with a DEM. Accuracy can be improved by using SRTM data and 3D distances. SRTM just requires a reprocess of the data, but 3D distance needs a feature addition in ProfileMaker

[nawagers]

I made some improvements to the SRTM library to include an inverse distance weighted interpolation and utilize SRTM v3 data (void-free). Elevation pages just need rebuilt.