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.
#!/bin/sh
mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m "test" -d "0 0"
hg verify
hg parents
hg status
hg undo
hg verify
hg parents
hg status