Vim 8.1 release

Update version number and information.  Fix a couple of tests.
diff --git a/src/gvim.exe.mnf b/src/gvim.exe.mnf
index 21ccfce..dd8f225 100644
--- a/src/gvim.exe.mnf
+++ b/src/gvim.exe.mnf
@@ -2,7 +2,7 @@
 <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3" >
   <assemblyIdentity
     processorArchitecture="*"
-    version="8.0.0.0"
+    version="8.1.0.0"
     type="win32"
     name="Vim"
   />