fixing missing clear function

fixing missing include

Author: eteran

bitset/include/cpp-utilities/bitset.h

@@ -26,6 +26,7 @@
 #define UTILITY_BITSET_HPP_
 
 #include <bitset>
+#include <cstdint>
 
 namespace bitset {
 

hash/include/cpp-utilities/sha1.h

@@ -149,7 +149,11 @@ class sha1 {
 		swap(state_, other.state_);
 	}
 
-	void clear();
+	void clear() {
+		digest_ = digest();
+		state_  = state();
+	}
+
 	digest finalize() const {
 		// make copies so this isn't a mutating operation
 		state s  = state_;