Add make.bat to make docs in windows.

docs/make.bat

@@ -0,0 +1,41 @@
+@echo off
+REM Minimal make.bat for Sphinx documentation
+REM You can set these variables from the command line.
+
+REM Set default variables
+set SPHINXOPTS=
+set SPHINXBUILD=sphinx-build
+set SPHINXPROJ=UltraPlot
+set SOURCEDIR=.
+set BUILDDIR=_build
+
+REM Check if no arguments were provided (show help)
+if "%1"=="" goto help
+
+REM Route to the appropriate target
+if "%1"=="help" goto help
+if "%1"=="clean" goto clean
+
+REM Catch-all target: route all unknown targets to Sphinx
+goto catchall
+
+
+:help
+REM Put it first so that "make" without argument is like "make help".
+%SPHINXBUILD% -M help "%SOURCEDIR%" "%BUILDDIR%" %SPHINXOPTS%
+goto :eof
+
+
+:clean
+REM Make clean ignore .git folder
+REM The /q doesn't raise error when files/folders not found
+if exist api\ rmdir /s /q api\
+if exist "%BUILDDIR%\html\" rmdir /s /q "%BUILDDIR%\html\"
+if exist "%BUILDDIR%\doctrees\" rmdir /s /q "%BUILDDIR%\doctrees\"
+goto :eof
+
+
+:catchall
+REM Route target to Sphinx using the "make mode" option
+%SPHINXBUILD% -M %1 "%SOURCEDIR%" "%BUILDDIR%" %SPHINXOPTS%
+goto :eof