Build - further automate windows build process

Still more work to be done here!

app/gui/qt/wix/BUILD_MSI.md

+# How to build an MSI installer using WiX
+
+1. Build `sonic-pi.exe` and run it to test.
+2. Copy wix directory to top level sonic-pi directory
+3. Remove files in `etc` and `app\gui` you don't want to include in the msi
+   - `app\gui` should likely only have the `release` and `theme` dirs, everything else can go
+4. Generate the wixobj files
+   - `wix\gen_wix.bat`
+5. Update version number
+   - edit wix\sonic-pi.wxs
+   - change version number (from X.Y.Z)
+6. Remove duplicate info
+   - edit `wix\gui.wxs`
+   - remove sonic-pi.exe component and componentref (both have identical IDs)
+7. Build the msi!
+   - `wix\gen_msi.bat`
+8. Your MSI should be found in the `wix` dir.
+

app/gui/qt/wix/gen_msi.bat

+cd %~dp0
+cd ..
+
+candle wix\sonic-pi.wxs etc.wxs gui.wxs server.wxs -ext WixUtilExtension
+light sonic-pi.wixobj etc.wixobj gui.wixobj server.wixobj -ext WixUtilExtension -ext WixUIExtension -o wix\Sonic-Pi.msi -b etc -b app\gui -b app\server

app/gui/qt/wix/gen_wix.bat

+cd %~dp0
+cd ..
+
+heat dir etc -gg -g1 -sfrag -dr SonicPi -cg ETC -out etc.wxs
+heat dir app\gui -gg -g1 -sfrag -dr AppDir -cg GUI -out gui.wxs
+heat dir app\server -gg -g1 -sfrag -dr AppDir -cg SERVER -out server.wxs
+
+echo Update version number in wix\sonic-pi.wxs
+echo Remove duplicate sonic-pi.exe info from wix\gui.wxs
+echo Then run gen_msi.bat

app/gui/qt/wix/sonic-pi.wxs

 <?xml version="1.0" encoding="utf-8"?>
 <Wix xmlns="http://schemas.microsoft.com/wix/2006/wi" xmlns:util="http://schemas.microsoft.com/wix/UtilExtension" xmlns:firewall="http://schemas.microsoft.com/wix/FirewallExtension">
 
-<!-- so you want to be a WiXard?
-
-1. Copy wix directory to top level sonic-pi directory
-
-2. Generate the wixobj files
-heat dir etc -gg -g1 -sfrag -dr SonicPi -cg ETC -out wix\etc.wxs
-heat dir app\gui -gg -g1 -sfrag -dr AppDir -cg GUI -out wix\gui.wxs
-heat dir app\server -gg -g1 -sfrag -dr AppDir -cg SERVER -out wix\server.wxs
-
-3. Update version number
-- edit wix\sonic-pi.wxs
-- change version number (from X.Y.Z)
-
-4. Remove duplicate info
-- edit wix\gui.wxs
-- remove sonic-pi.exe component and componentref (both have identical IDs)
-
-5. Prepare the candle?!?
-candle wix\sonic-pi.wxs wix\etc.wxs wix\gui.wxs wix\server.wxs -ext WixUtilExtension
-
-6. Build the msi!
-light sonic-pi.wixobj etc.wixobj gui.wixobj server.wixobj -ext WixUtilExtension -ext WixUIExtension -o wix\Sonic-Pi.msi -b etc -b app\gui -b app\server
-
--->
-
   <Product Id="*" Name="Sonic Pi" Language="1033" Version="X.Y.Z" Manufacturer="Sonic Pi" UpgradeCode="ECA5D03B-CEBD-4672-A0A2-176CBCBA4429">
     <Package Description="Sonic Pi Installer" Comments="Sonic Pi Installer" InstallScope="perMachine" InstallerVersion="200" Compressed="yes" />
     <Property Id="REINSTALLMODE" Value="amus"/>
@@ -33,9 +8,9 @@ light sonic-pi.wixobj etc.wixobj gui.wixobj server.wixobj -ext WixUtilExtension
     <MajorUpgrade AllowDowngrades="yes" Schedule="afterInstallInitialize"/>
     <Media Id="1" Cabinet="simple.cab" EmbedCab="yes" />
 
-    <WixVariable Id="WixUILicenseRtf" Value="LICENSE.rtf" />
-    <WixVariable Id="WixUIBannerBmp" Value="wix_ui_banner.bmp" />
-    <WixVariable Id="WixUIDialogBmp" Value="wix_ui_dialog.bmp" />
+    <WixVariable Id="WixUILicenseRtf" Value="wix\LICENSE.rtf" />
+    <WixVariable Id="WixUIBannerBmp" Value="wix\wix_ui_banner.bmp" />
+    <WixVariable Id="WixUIDialogBmp" Value="wix\wix_ui_dialog.bmp" />
     <Property Id='ARPCONTACT'>https://in-thread.sonic-pi.net</Property>
     <Property Id='ARPHELPLINK'>https://in-thread.sonic-pi.net</Property>
     <Property Id='ARPURLINFOABOUT'>http://sonic-pi.net</Property>