streamWrapper::rmdir — Removes a directory
This method is called in response to rmdir().
In order for the appropriate error message to be returned this method should not be defined if the wrapper does not support removing directories.
The directory URL which should be removed.
A bitwise mask of values, such as STREAM_MKDIR_RECURSIVE.
Returns TRUE on success or FALSE on failure.
Emits E_WARNING if call to this method fails (i.e. not implemented).
The streamWrapper->context property is updated if a valid context is passed to the caller function.