Replace Generate*.bat files with a single generate.sh which uses VS2019 by default

build/Generate.bat

@@ -1,39 +0,0 @@
-@echo off
-goto menu
-
-:menu
-echo Build Project Generator:
-echo.
-echo [0] Clean
-echo [1] Visual C++ 2019
-echo [2] Visual C++ 2017
-echo [3] GNU Make
-
-echo.
-
-:choice
-set /P C="Choice: "
-if "%C%"=="0" goto clean
-if "%C%"=="1" goto vs2019
-if "%C%"=="2" goto vs2017
-if "%C%"=="3" goto gmake
-
-:clean
-"premake5" --file=premake5.lua clean
-goto quit
-
-:vs2019
-"premake5" --file=premake5.lua vs2019
-goto quit
-
-:vs2017
-"premake5" --file=premake5.lua vs2017 
-goto quit
-
-:gmake
-"premake5" --file=premake5.lua gmake
-goto quit
-
-:quit
-pause
-:end

build/GenerateMake.bat

@@ -1,5 +0,0 @@
-@echo off
-
-premake5 --file=premake5.lua gmake
-
-pause

build/GenerateVS2019.bat

@@ -1 +0,0 @@
-"premake5" --file=premake5.lua vs2019

build/generate.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+set -e
+DIR=$( cd "$( dirname "$0" )" && pwd )
+$DIR/build.sh generate "$@"