Some Release Notes cleanup.

- Fix bug link to bug 1814.
- Fix the wiki's URL (the wiki doesn't appear to support https today).
- Remove bugs 4445 and 9242 from the Known Problems list: they've been fixed.

Change-Id: Idd870a9d409eff4916ca7d6a1cd6aa38b4dd875d
Reviewed-on: https://code.wireshark.org/review/4405
Reviewed-by: Jeff Morriss <jeff.morriss.ws@gmail.com>