fleshed out GetVar, added Token stack collection, started printing module

pkg/shsh/stack.go

@@ -0,0 +1,22 @@
+package shsh
+
+type TokenStack struct {
+    buffer []*Token
+    int capacity
+}
+
+func (s *Stack) Push(v *Token) {
+    s.capacity++
+    *s.buffer = append(*s.buffer, v)
+}
+
+func (s *Stack) Pop() *Token {
+    if s.capacity <= 0 {
+        return nil
+    }
+
+    s.capacity--
+    res := *s.buffer[len(*s.buffer) - 1]
+    *s = *s.buffer[ :len(*s) - 1]
+    return ret
+}