Add intToString() and stringToInt() functions

src/solstice_stdlib.cpp

@@ -28,6 +28,22 @@ def println(string msg) string {
     return msg
 }
 
+def stringToInt(string in) int {
+    result = 0
+    ground {
+        stoi $in &result
+    }
+    return result
+}
+
+def intToString(int in) string {
+    result = ""
+    ground {
+        tostring $in &result
+    }
+    return result
+}
+
 // End Solstice stdlib
 
     )";