Introduce 'exclude_tags' (#124)

* added option for skip_tags var to omit objects

* documented skip_tags in openshift_applier README

* changed skip_tags to exclude_tags and allowed for use with filter_tags

* fixed newline error

* changed refrences in filter from filter_tags to include_tags

* fixed filter_content function name

* fixed include_list var

* handle overlapping invocation of include_tags and exclude_tags with erroring out

* added newline for ci job

* same as before

* removed blank line

* remove trailing white space

* updated error messages and default filter values

* updated filter error