Made the set tag work to local variables. Moved tests to their own directory.

tests/testvar.jet

@@ -0,0 +1,16 @@
+#!../jet-2.0
+<jet filterblanklines="true" trimlines="true">
+<set name="ix" value="1" />
+<set name="letterx" value="x" />
+<set name="var1" value="this is a test" />
+<set name="1var1" value="This is another test" />
+<set name="var1var" value="Yet another test" />
+<set name="var11" value="it seems to work." />
+$[$[ix]var$[ix]]
+$[var$[ix]]
+$[var$[ix]var]
+$[var$[i$[letterx]]var]
+$[letterx;TOHEX]
+$[var$[i$[letterx]]$[ix]]
+$[var$[i$[letterx]]$[i$[letterx]]]
+</jet>