Relax validation of -BETA / -RC releases

Accross the code, release names are checked against some variation of
-BETAx / -RCx which are inconsistent in the range of accepted values for
`x`.

As  a consequence, some commands cannot be successfuly run while they
are valid, e.g. `bastille create test 14.0-RC4 10.0.0.2` is rejected
because only `*-RC1` and `*-RC2` are accepted as a RC release name.

Find out these lists of specific BETA and RC patterns and adjust them to
allow any one-digit value at the end.  We generaly do up to 4 BETA / RC
releases, so a one digit limit is probably enough for the time being.

usr/local/share/bastille/rename.sh

@@ -83,7 +83,7 @@ update_fstab() {
     if [ -f "${FSTAB_CONFIG}" ]; then
         # Skip if fstab is empty, e.g newly created thick or clone jails
         if [ -s "${FSTAB_CONFIG}" ]; then
-            FSTAB_RELEASE=$(grep -owE '([1-9]{2,2})\.[0-9](-RELEASE|-RC[1-2])|([0-9]{1,2}-stable-build-[0-9]{1,3})|(current-build)-([0-9]{1,3})|(current-BUILD-LATEST)|([0-9]{1,2}-stable-BUILD-LATEST)|(current-BUILD-LATEST)' "${FSTAB_CONFIG}")
+            FSTAB_RELEASE=$(grep -owE '([1-9]{2,2})\.[0-9](-RELEASE|-RC[1-9])|([0-9]{1,2}-stable-build-[0-9]{1,3})|(current-build)-([0-9]{1,3})|(current-BUILD-LATEST)|([0-9]{1,2}-stable-BUILD-LATEST)|(current-BUILD-LATEST)' "${FSTAB_CONFIG}")
             FSTAB_CURRENT=$(grep -w ".*/releases/.*/jails/${TARGET}/root/.bastille" "${FSTAB_CONFIG}")
             FSTAB_NEWCONF="${bastille_releasesdir}/${FSTAB_RELEASE} ${bastille_jailsdir}/${NEWNAME}/root/.bastille nullfs ro 0 0"
             if [ -n "${FSTAB_CURRENT}" ] && [ -n "${FSTAB_NEWCONF}" ]; then