Feature: Add variable to allow hardtime to ignore quickfix window

Added a separate variable to allow hardtime to ignore the quickfix
window. Since the quickfix window does not return a value from
`bufname("%")` attempting to add it to `hardtime_ignore_buffer_patterns`
is not effective.
Merge pull request #22 from JarrodCTaylor/master

Feature: Add variable to allow hardtime to ignore quickfix window