Added strf validation

src/utils/strfparse.h

@@ -0,0 +1,20 @@
+#include <algorithm>
+#include <ctime>
+#include <map>
+#include <sstream>
+#include <vector>
+
+namespace strfparse {
+std::vector<std::string> split(std::string const& s, char delimiter);
+
+std::vector<char> create_specifier_list();
+
+std::string replace_all(std::string input,
+                        std::string const& to_find,
+                        std::string const& to_replace);
+
+std::vector<char> match_specifiers(std::string const& specifier,
+                                   std::vector<char> allowed_specifier);
+
+std::string format_time_string(std::string const& specifier);
+}