Make tests of escaped file and folder names more flexible.

[phil-davis]

See cs3org/reva#1425

There are tests that check the d:href string that is returned in PROPFIND or other API requests. If the file path contains "special characters" then those have been escaped. For example, a space character is escaped as %20, a question mark is escaped as %3F or %3f

https://tools.ietf.org/html/rfc3986#section-2.1 specifies that this escaping/encoding is not case-sensitive. %3F and %3f are both valid representations of ?.

Find the places in the core API test suite where the tests are currently "too fussy". Make those tests case-insensitive.

This will help when testing against other implementations like OCIS.