[https] Allow configuration of anonymous access on https (closes #1971992) For now any anonymous access in denied on secured connection (https-url). This patch introduce a configuration option to control this behaviour. New instance will allow it. Old instance should stay as is during migration.

[bfss] convert root BFSS directory to str in constructor (closes #2137793) otherwise you can get crashed with AssertionError: Binary objects must use raw strings, not <type 'unicode'>

[rql, security] fix buggy rqlstr cleanup when some introduced snippet create an unresolvable query. Closes #2142041