A Vader issue causes problems with the test results when using the
location list. Because of this the tests were modified to run 1 test
file per vim instance instead of running all tests in a single vim
instance. This resulted in signficant slow down in test execution time.
To speed up execution time only specific tests are run individually now.
- Create function wrapper around lvimgrep for input checking, pattern
quoting, and error handling.
- Add Vader tests for VimwikiSearch.
- Change syntax loading from try/catch to explicit file check (to
prevent Vader test bug).
- Update doc/vimwiki.txt for changes.
- Change test script to run Vader tests separately
