WinRT: removed '-' from build script file names

Most of the other build scripts don't include a '-' in their file names.  This
change makes the WinRT build scripts use the same convention.

build-scripts/winrt-build.bat → build-scripts/winrtbuild.bat

@@ -1,8 +1,8 @@
 @ECHO OFF
 REM
-REM winrt-build.bat: a batch file to help launch the winrt-build.ps1
+REM winrtbuild.bat: a batch file to help launch the winrtbuild.ps1
 REM   Powershell script, either from Windows Explorer, or through Buildbot.
 REM
 SET ThisScriptsDirectory=%~dp0
-SET PowerShellScriptPath=%ThisScriptsDirectory%winrt-build.ps1
+SET PowerShellScriptPath=%ThisScriptsDirectory%winrtbuild.ps1
 PowerShell -NoProfile -ExecutionPolicy Bypass -Command "& '%PowerShellScriptPath%'";

build-scripts/winrt-build.ps1 → build-scripts/winrtbuild.ps1

@@ -1,11 +1,11 @@
 #
-# winrt-build.ps1 -- A Powershell script to build all SDL/WinRT variants,
+# winrtbuild.ps1 -- A Powershell script to build all SDL/WinRT variants,
 #    across all WinRT platforms, in all of their supported, CPU architectures.
 #
 # Initial version written by David Ludwig <dludwig@pobox.com>
 #
 # This script can be launched from Windows Explorer by double-clicking
-# on winrt-build.bat
+# on winrtbuild.bat
 #
 # Output will be placed in the following subdirectories of the SDL source
 # tree: