Added Include folder

*facepalm*

include/cmd/cmd_tr.hpp

@@ -0,0 +1,74 @@
+#pragma once
+
+#include "cmd/args/arg.hpp"
+#include "cmd/args/arg_generic.hpp"
+#include "cmd/args/arg_input.hpp"
+#include "cmd/args/arg_manager.hpp"
+#include "cmd/cmd_base.hpp"
+#include "util/input.hpp"
+#include "util/stringliteral.hpp"
+#include <algorithm>
+#include <iostream>
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+namespace fsh {
+
+    class CmdTr : public Command {
+      public:
+        virtual void execute(FlagNode flag, ArgNodes& vec, std::istream& in, std::ostream& out) override {
+            ArgFactory af;
+            switch (vec.size()) {
+                case 2: 
+                    af.add_rule<StringLiteral>(1);
+                case 1: 
+                    af.add_rule<StringLiteral>(1);
+                    break;
+                
+                default:
+                    af.add_input_rule();
+                    af.add_rule<StringLiteral>(1);
+                    af.add_rule<StringLiteral>(1);
+                    break;
+            }
+            Command::execute(flag, vec, in,out, af);
+        }
+
+      protected:
+
+        std::string replace_all(std::string str,const std::string &what,const std::string &with) {
+            if(what == "") throw std::runtime_error("\"\" cannot be used as what");
+
+            unsigned long long pos = str.find(what);
+
+            while(pos != std::string::npos) {
+                str.replace(pos,what.size(),with) ;
+                pos = str.find(what,pos+with.size());
+            }
+            return str;
+        }
+
+        virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
+            std::string s;
+            std::string o;
+            std::string what = "";
+            std::string with = "";
+            while (std::getline(in, s)) { o += s + "\n"; }
+            
+            switch (args.size()) {
+                case 2:
+                    with = args.get<StringLiteral>(1).value();
+                case 1:
+                    what = args.get<StringLiteral>(0).value();
+                    break;
+                case 3:
+                    what = args.get<StringLiteral>(1).value();
+                    with = args.get<StringLiteral>(2).value();
+            }
+
+            out << replace_all(o,what,with);
+        }
+    };
+
+}