+ Preparations to support more target languages. Tested with Swedish.
+ Don't enable example-based editing if there is less that two concrete
languages in the grammar.
+ Don't show the "By example" button until the required lincat has been defined.
+ Remember the chosen language for examples.
"gf -server" mode now includes PGF service and the services to support
example-based grammar writing. (But gf -server is not quite ready to replace
pgf-http yet...)
Also bumped GF version number to 3.2.10-darcs
The editor needs to keep track of both the raw term and the nice term returned
by exprToAPI. (Manually constructed linearization rules will now have the
raw term and can not be tested.)
Also replace metavariables in generalized terms with the apropriate parameter
from the linearization rule.
Also fix communication problems caused by inconsistent use of show/read vs
showExpr/readExpr.