Fix interaction of various --exclude-tag options with --listed-incremental.

Fix interaction of various --exclude-tag options with --listed-incremental.

* src/incremen.c (procdir): Set directory->tagfile in
the exclusion_tag_contents case.
(makedumpdir): Mark all entries as ignored if directory->tagfile
is set.
Free new_dump before returning.
(maketagdumpdir): New function.
(scan_directory): If directory->children is set to
NO_CHILDREN and directory->tagfile is set, create a
dumpdir consisting of the tagfile only.

* tests/exclude08.at: New testcase.
* tests/exclude09.at: New testcase.
* tests/exclude10.at: New testcase.
* tests/exclude11.at: New testcase.
* tests/exclude12.at: New testcase.
* tests/exclude13.at: New testcase.
* tests/exclude14.at: New testcase.
* tests/exclude15.at: New testcase.
* tests/exclude16.at: New testcase.
* tests/Makefile.am: Add new tests.
* tests/testsuite.at: Include new tests.
* tests/atlocal.in (mkexcltest): New function.
* tests/chtype.at: Update keywords.
* tests/filerem01.at: Likewise.
* tests/filerem02.at: Likewise.
* tests/incremental.at: Likewise.
* tests/multiv04.at: Likewise.