Fix some quote inset bugs:

Fix some quote inset bugs:

* Adjoining closing Single + double quote becomes double + single quote
  (for English, Swedish and German, LaTeX export as ''').

* French double quotes are converted to << >> in the LaTeX file and to
  double inverted question/interrogation marks in the output, if the font
  encoding is set to [None] or OT1 but the global default is T1. (test
  for lyxrc.fontenc instead of the document-specific fontenc setting in
  InsetQuotes.cpp).

* Quote type ignored for LyXHTML: always "English" quotes used.

See #10451