fixed missing #include <utility>

also:
- added test for `yaml_formatter`
- formatter refactoring + cleanup
- documentation fixes

tools/clang_format.bat

@@ -4,16 +4,27 @@ PUSHD .
 CD /d "%~dp0\.."
 
 REM --------------------------------------------------------------------------------------
-REM 	Runs clang format on all the non-test C++ files in the project
+REM 	Runs clang format on all the C++ files in the project
 REM --------------------------------------------------------------------------------------
 
+WHERE /Q clang-format
+IF %ERRORLEVEL% NEQ 0 (
+	ECHO Could not find clang-format
+	PAUSE
+	POPD
+	ENDLOCAL
+	EXIT /B %ERRORLEVEL%
+)
+
 CALL :RunClangFormatOnDirectories ^
 	include\toml++ ^
 	include\toml++\impl ^
 	tests ^
 	examples
 
-GOTO FINISH
+POPD
+@ENDLOCAL
+EXIT /B 0
 
 :RunClangFormatOnDirectories
 (
@@ -27,8 +38,3 @@ GOTO FINISH
 	)
 	EXIT /B
 )
-
-:FINISH
-POPD
-@ENDLOCAL
-EXIT /B 0

tools/requirements.txt

@@ -1,4 +1,4 @@
 misk>=0.5.0
-poxy>=0.5.1
+poxy>=0.5.2
 pyyaml
 python-dateutil