build(build.bat): fix boost build, add config template for vs2019

update boost libraries for vs2019 support;
use b2.exe instead of bjam.exe for recent versions of boost.

build.bat

@@ -149,14 +149,14 @@ set BJAM_OPTIONS_X64=%BJAM_OPTIONS_COMMON%^
 
 if %build_boost% == 1 (
   cd /d %BOOST_ROOT%
-  if not exist bjam.exe call bootstrap.bat
+  if not exist b2.exe call bootstrap.bat
   if errorlevel 1 goto error
 
-  bjam %BJAM_OPTIONS_X86% stage %BOOST_COMPILED_LIBS%
+  b2 %BJAM_OPTIONS_X86% stage %BOOST_COMPILED_LIBS%
   if errorlevel 1 goto error
 
   if %build_boost_x64% == 1 (
-    bjam %BJAM_OPTIONS_X64% stage %BOOST_COMPILED_LIBS%
+    b2 %BJAM_OPTIONS_X64% stage %BOOST_COMPILED_LIBS%
     if errorlevel 1 goto error
   )
 )

env.vs2017_xp.bat

@@ -0,0 +1,14 @@
+rem Customize your build environment and save the modified copy to env.bat
+
+set RIME_ROOT=%CD%
+
+rem REQUIRED: path to Boost source directory
+set BOOST_ROOT=C:\Libraries\boost_1_69_0
+
+rem OPTIONAL: Visual Studio version and platform toolset
+set BJAM_TOOLSET=msvc-14.1
+set CMAKE_GENERATOR="Visual Studio 15 2017"
+set PLATFORM_TOOLSET=v141_xp
+
+rem OPTIONAL: path to additional build tools
+rem set DEVTOOLS_PATH=%ProgramFiles%\Git\cmd;%ProgramFiles%\CMake\bin;C:\Python27;

env.vs2019.bat

@@ -0,0 +1,14 @@
+rem Customize your build environment and save the modified copy to env.bat
+
+set RIME_ROOT=%CD%
+
+rem REQUIRED: path to Boost source directory
+set BOOST_ROOT=C:\Libraries\boost_1_76_0
+
+rem OPTIONAL: Visual Studio version and platform toolset
+set BJAM_TOOLSET=msvc-14.2
+set CMAKE_GENERATOR="Visual Studio 16 2019"
+set PLATFORM_TOOLSET=v142
+
+rem OPTIONAL: path to additional build tools
+rem set DEVTOOLS_PATH=%ProgramFiles%\Git\cmd;%ProgramFiles%\CMake\bin;C:\Python27;