handle missing qnodes or qedges

[patrickkwang]

Fixes #3.

[patrickkwang]

Also fixes #5.

[codecov]

Codecov Report

Merging #13 into master will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master       #13   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            4         4           
  Lines          303       310    +7     
=========================================
+ Hits           303       310    +7     

Impacted Files	Coverage Δ
reasoner/cypher.py	100.00% <100.00%> (ø)
reasoner/nesting.py	100.00% <100.00%> (ø)

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[maximusunc]

Something to discuss: if the user passes in a qgraph that is missing nodes or edges, we aren't catching that and the application will error when trying to mapize the qgraph. Do we want some sort of check to make sure those properties are there? The error thrown is a KeyError.

[maximusunc]

👍