Handle Appendix Section Updates

This extends appendix compilation to account for edits to an appendix section (e.g. A-33 or B-4(C) or C-19(A)(3)). This requires refactoring some other parts of the parser, notably standardizing on the assumption that "A-33(A)(3)" means a single appendix section (rather than section 33, paragraph (A), subparagraph (3)). This isn't always true, but I've found it to be the case more often than not.

Other Details:
* Auto generate intermediary sections in phrases like "A-33(A)(1) through A-33(A)(6)"
* Account for "heading of A-33" in amdpars
* Account for single appendix sections in amdpars
* Do not duplicate appendix parsing
* Exclude "www." as a paragraph marker