SourceInformation improvements

[kevin-m-knight-gs]

Add several methods to SourceInformation: intersects, isValid, and a suite of methods for comparing source positions (i.e., line-column pairs).

[github-actions[bot]]

Test Results

   546 files  ±0     546 suites  ±0   28m 23s :stopwatch: -15s 4 059 tests +8  4 029 :heavy_check_mark: +8  30 :zzz: ±0  0 :x: ±0  5 438 runs  +8  5 408 :heavy_check_mark: +8  30 :zzz: ±0  0 :x: ±0 

Results for commit 7ee59875. ± Comparison against base commit d1cbc36e.