many small changes to templater.
get string code to parse escapes. uses eval now, should parse strings
itself soon.
let caller check if fragment is defined using "in".
make templatepath take optional file name.
%%% should show a removed and b added
A b
R a
reverting...
%%% should show b unknown and a back to normal
? b
merging a
%%% should show foo-b
foo-b
%%% should show a removed and b added
A b
R a
reverting...
%%% should show b unknown and a marked modified (merged)
? b
%%% should show foo-b
foo-b