Based on the feedback from Mark, I've left the languages 
passing in a string, shortened to "gxx" etc.  That does
put off the decision where and when to use the dwarf2 enum.

Based on the feedback from the GNAT folk, I've renamed
the Ada personality routine to match the other languages.

I expect the full testsuite run for x86_64-linux to complete
within the next hour.  Ok to commit assuming the results 
look good?


r~