Laid ground work for resolveKeyword method on Tag and to not resolve automatically.

tests/testvar.jet

@@ -1,12 +1,10 @@
 #!../jet-2.0
-<jet filterblanklines="true" trimlines="true">
-<set name="ix" value="1" />
+ <set name="ix" value="1" />
 <set name="letterx" value="x" />
-<set name="var1" value="this is a test" />
+<set name="var$[ix]" value="this is a test $[ix]" />
 <set name="1var1" value="This is another test" />
 <set name="var1var" value="Yet another test" />
 <set name="var11" value="it seems to work." />
-$[$test]
 $[$[ix]var$[ix]]
 $[var$[ix]]
 $[var$[ix]var]
@@ -14,4 +12,4 @@ $[var$[i$[letterx]]var]
 $[letterx;TOHEX]
 $[var$[i$[letterx]]$[ix]]
 $[var$[i$[letterx]]$[i$[letterx]]]
-</jet>
+