Add auto-generated Git version to window titles

src/scmversion/gen_scmversion.bat

@@ -0,0 +1,23 @@
+@echo off
+
+SET VERSIONFILE="scmversion.cpp"
+FOR /F "tokens=* USEBACKQ" %%g IN (`git rev-parse --abbrev-ref HEAD`) do (SET "BRANCH=%%g")
+FOR /F "tokens=* USEBACKQ" %%g IN (`git describe --tags --dirty`) do (SET "TAG=%%g")
+
+SET SIGNATURELINE=// %BRANCH% %TAG%
+SET /P EXISTINGLINE=< %VERSIONFILE%
+
+IF "%EXISTINGLINE%"=="%SIGNATURELINE%" (
+  ECHO Signature matches, skipping writing %VERSIONFILE%
+  EXIT
+)
+
+ECHO Updating %VERSIONFILE%...
+
+(ECHO %SIGNATURELINE%
+ECHO const char* g_scm_branch_str = "%BRANCH%";
+ECHO const char* g_scm_tag_str = "%TAG%";
+)>%VERSIONFILE%
+
+EXIT
+