Swap 'title' and 'releaseTitle' meaning

- Trasparent change: now it makes more sense.
- Updated tests to reflect 'title', 'releaseTitle' meaning swap.
- Improved documentation.

Signed-off-by: JoeLametta <JoeLametta@users.noreply.github.com>

man/whipper-cd-rip.rst

@@ -96,7 +96,8 @@ Template schemes
 | - %S: release sort name
 | - %B: release barcode
 | - %C: release catalog number
-| - %d: disc title
+| - %d: release title (with disambiguation)
+| - %D: disc title (without disambiguation)
 | - %y: release year
 | - %r: release type, lowercase
 | - %R: release type, normal case