Renaming of 'MergedPartialTestVectorRepresentations' to 'SetOfMergedPaths'.
'Vector' to 'Path' rename for file being broken out only.
Rename of 'Level' to 'Step'.
Rename 'TestVector' to 'Path'.
Addendum to previous rename commit.
Renaming stragglers in the implementation file. Still have to finish off in the tests file.
Renames in test code to match what's under test.
Break out 'SetOfMergedPaths' into the 'SageSerpent.Infrastructure' assembly.