add icon to windows EXE (#97)

Author: shueybubbles

README.md

@@ -107,7 +107,7 @@ The version on the binary will match the version tag of the branch.
 
 ```sh
 
-go install https://github.com/tc-hib/go-winres
+go install github.com/tc-hib/go-winres@latest
 cd cmd/sqlcmd
 go generate
 

cmd/sqlcmd/winres/winres.json

@@ -1,4 +1,9 @@
 {
+  "RT_GROUP_ICON": {
+    "APP": {
+      "0000" : "../../../release/windows/msi/resources/sqlcmd.ico"
+    }
+  },
   "RT_VERSION": {
     "#1": {
       "0000": {