Feature/deregister plugin path pathlib support

[hannesdelbeke]

add deregister plugin path support

also took the chance to clean up and extend (de)register path tests now not limitted to just pathlib there is a single legacy test for deregister path, but no tests yet for register path AFAIK

split tests into:

• register path test
• register path (pathlib) test
• deregister path (pathlib) test
• deregister path test

following PR is branched from UX improvements, not master, and should be merged in only after PR 380 is in. i'll cleanup PR later in case of conflict

tests should fail on deregister path (pathlib) test have tests running locally but want to confirm

[hannesdelbeke]

ok weird stuff happening

• pathlib register path test, runs fine
• pathlib deregister path test, doesnt even attempt to run it. nor is it in the log marked as skipped

have the same happen locally. not sure why

[hannesdelbeke]

second weird thing. relates to https://github.com/pyblish/pyblish-base/issues/379

after extending the register plugin path tests with more samples it fails on the following example string you provided last time

u"c:\some\special\södär\testpath".encode('utf-8')

AssertionError: b'c:\some\special\s\xc3\xb6d\xc3\xa4r\testpath' not in ['C:\\projects\\pyblish\\pyblish\\plugins', 'server\\plugins', b'c:\\some\\special\\s\xc3\xb6d\xc3\xa4r\testpath']

this only happens with python 3

[hannesdelbeke]

since there are 2 separate issues i'll move the binary string tests to a new PR

[hannesdelbeke]

when removing the tests for the binary string the test suite works as expected again. how odd. created a new branch to PR from (oh and this is not related to the commit above, working in a new branch)

[hannesdelbeke]

closing this PR and creating 2 new ones. for clarity pathlib (de)registration is now clean (branched from master) and working as expected