ch_root, ch_root_via: Documented that these are usually not idempotent operations

mappings/VegX-VegBIEN.stems.csv: input (VegX) root: Removed tcs namespace URL to simplify the XPath reversing process. It isn't needed now that we don't generate intermediate XML documents in the automated tests (because intermediate formats are no longer required to be XML schemas).

mappings/DwC2-VegBIEN.specimens.csv: Reversed XPaths so that they start with location instead of specimenreplicate

README.TXT: WinMerge setup: Documented how to get to Compare Options page

README.TXT: WinMerge setup: Added step to set Whitespace to Ignore change

README.TXT: Moved WinMerge setup to separate section. Changed Moved block detection link to the Configuration page.

mappings/VegX-VegBIEN.stems.csv: Expanded {} expressions using expand_braces, so that each distinct output for the same input is on its own line, improving readability. This will also help enable search-and-replace reversing of XPaths for the re-rooting to location.

mappings/VegX-VegBIEN.stems.csv: VegX XPaths: Expanded {} expressions using expand_braces, so that later use of expand_braces on the file would not affect the VegX output mappings of the inputs' via maps (VegX.organisms.csv, etc.)

mappings/DwC2-VegBIEN.specimens.csv: Expanded {} expressions using expand_braces, so that each distinct output for the same input is on its own line, improving readability. This will also help enable search-and-replace reversing of XPaths for the re-rooting to location.

README.TXT: Accepting test cases: Documented that when refactoring mappings, it's helpful to use WinMerge to detect moved lines