This fixes several problems with how the builtin `history` command handles
arguments. It now complains and refuses to do anything if the user specifies
incompatible actions (e.g., `--search` and `--clear`). It also fixes a
regression introduced by previous changes with regard to invocations that
don't explicitly specify `--search` or a search term.
Enhances the history man page to clarify the behavior of various options.
This change is already far larger than I like so unit tests will be added
in a separate commit.
Fixes#3224.
Note: This fixes only a couple problems with the interactive `history
--delete` command in the `history` function. The main problem will be
dealt with via issue #31.
