Add find support to std::string

tstl/include/string.hpp

@@ -28,6 +28,8 @@ public:
     typedef CharT*             iterator;
     typedef const CharT*       const_iterator;
 
+    static constexpr const size_t npos = -1;
+
 private:
     size_t _size;
     size_t _capacity;
@@ -227,6 +229,16 @@ public:
         return _data[i];
     }
 
+    size_t find(char c) const {
+        for(size_t i = 0; i < size(); ++i){
+            if(_data[i] == c){
+                return i;
+            }
+        }
+
+        return npos;
+    }
+
     //Operators
 
     bool operator==(const CharT* s) const {