Fix inputencoding for documentation, examples, and templates.

Fix inputencoding for documentation, examples, and templates.

* "platex" fails with "inputencoding default", if there is text in other languages.
  "jis-platex" works fine, "jis-utf8" fails with German Umlauts (maybe more).

* The expert setting "inputencoding default" switches the inpute encoding
  with language switches without marking this in the LaTeX source.
  It is rarely required (if ever) and makes documents easy to break.

  It is not required for AMS Books, Simple CV, ... (probabely a tex2lyx issue).
  "utf8" and "auto" work fine.