* Implement feature "Search multiple tags, exclusion in tag search"
Add failing test for searching any multiple set of tags
Search any tags works; passing tests
Add failing test for searching all multiple tags
Search all tags works
Do not allow combination of search logics
Adds support for tag exclusion search
Update Search Options Group
Update README
Clean up
Fix man/readme language
Fix search_by_tag docstring
Split tags by ' - ' not '-': allows for hyphenation
Remove unnecessary else
Change search_logic lang to search_operator
Update exclusion language in readme and man
Print warning if ',' and '+' are both used in a search
* Add documentation and examples to manpage, improve documentation in README and buku.py
* Enforce space separation of '+' and document
* Fix under-indent in tests that causes build failure
* Add test to check that search_by_tag constructs correct sqlite query; also remove unittest.skips from search_by_tag tests
* Move tag search preparation work into prep_tag_search helper function; add test to test_buku.py
* Use pytest.mark.parametrize for test_prep_tag_search
* fix: dev: os function name
* new: test: pylint config
* new: test: pylint test
* chg: dev: linting guide
* new: dev: add alternative commented test run command
* chg: dev: max line length on PR template
* WIP import bookmarks from browser database files
* WIP Import chrome bookmarks from browser
* Implement import from FF function
* Add default GC and FF folders for Linux, OS X and Windows
* Remove unused function
* Close file after usage
* Fix uncareful merge
* Fix merge conflicts, fix styling
* Add blank lines between functions
* Add new lines in docstrings
* Rename argument for auto import
* WIP import bookmarks from browser database files
* WIP Import chrome bookmarks from browser
* Implement import from FF function
* Add default GC and FF folders for Linux, OS X and Windows
* Remove unused function
* Close file after usage
* Fix uncareful merge
* Fix merge conflicts, fix styling
* Add blank lines between functions
* Add new lines in docstrings
* reqs: Lower bound hypothesis
Hypothesis should be lower bound instead of being fixed at 3.7.0
* chg: test: set min requirement for pytest
* chg: test: upgrade pip on travis
* chg: test: upgrade setuptools on travis
* chg: test: add py as test req on travis
