parseUserInfo removed from getPassword and getUser
isValid override removed
building userinfo by user and password
trailing spaces removed
#6886 - simplifying logic, minor CS and docblock fixes
#6886 - adding `@group` annotation to newly introduced tests
#6886 - `assertSame` over `assertEquals`
#6886 - typo fix (useless assignment caused by copy/paste)
#6886 - should allow null user and password being set
#6886 - should allow null userInfo fragment
#6886 - setting `null` `userInfo`, `user` or `password` should be reflected in internal object state
Merge branch 'feature/#6886-zend-uri-http-password-support' into develop

Close #6886