Help for reporting options is now also defined once in lib.m4
(in addition to CliOptions.hs). Also fixed some duplication of general
options in docs. hledger-* manuals now include the full list of general
and reporting options; we assume that any inapplicable options get
harmlessly ignored and that this will not surprise users.
Use slightly clearer m4 macros instead of special divs to mark content
as web only/man only. The temporary doc/*.md files are no longer needed,
slightly more redundant work is done.
