for loops

test/circuits/forrolled.circom

@@ -0,0 +1,14 @@
+template ForRolled() {
+    signal input in;
+    signal output out;
+
+    var acc = 0;
+
+    for (var i=0; i<in; i = i+1) {
+        acc = acc + 1;
+    }
+
+    out <== acc;
+}
+
+component main = ForRolled();