Bug 17245: Untranslatable abbreviated names of seasons.

Bug 17245: Untranslatable abbreviated names of seasons.

Because seasons strings are not available through DateTime module,
names of them where added in code, and templates. Bug 16289 adds new
abbreviated form to the code, but not to the templates. This patch
should fix the problem.

To test:
1. Apply patch.
2. Run "misc/translator/translate update" for you language.
3. Check if names are in po/ file for language.
4. Check if generating next issue for serial and prediction patterns
works correct.

NOTE: or "create {language code}" instead of update.

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Katrin Fischer  <katrin.fischer@bsz-bw.de>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>