Upgrade to sqlite3 3.7.4.
diff --git a/PCbuild/pyproject.vsprops b/PCbuild/pyproject.vsprops
index 52cef12..2ec9fdd 100644
--- a/PCbuild/pyproject.vsprops
+++ b/PCbuild/pyproject.vsprops
@@ -50,7 +50,7 @@
 	/>
 	<UserMacro
 		Name="sqlite3Dir"
-		Value="$(externalsDir)\sqlite-3.6.21"
+		Value="$(externalsDir)\sqlite-3.7.4"
 	/>
 	<UserMacro
 		Name="bz2Dir"