LightGraphs => Graphs, GeoData => Rasters, some changes to type names

[vlandau]

Straightforward PR -- updated from LightGraphs to Graphs. Move from GeoData to Rasters. A couple of type names were also changed:

• SimpleRasterGraph => RasterGraph
• SimpleRasterDiGraph => RasterDiGraph

[codecov-commenter]

Codecov Report

Merging #5 (8b96328) into main (b7457a4) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main       #5   +/-   ##
=======================================
  Coverage   97.68%   97.68%           
=======================================
  Files           5        5           
  Lines         173      173           
=======================================
  Hits          169      169           
  Misses          4        4           

Impacted Files	Coverage Δ
src/utils.jl	100.00% <ø> (ø)
src/graph_interface.jl	95.83% <100.00%> (ø)
src/rastergraphs.jl	97.56% <100.00%> (ø)
src/show.jl	100.00% <100.00%> (ø)
src/structs.jl	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b7457a4...8b96328. Read the comment docs.