Allow Edge to edit local .js files

Edge has blocked .user.js from being previewed in the browser.
Hence, we can rename the file extension to be .js (remove .user) to
ensure Edge display the script inside browser.
This partially solves #156, not perfectly.

app/src/main/java/org/matrix/chromext/utils/Url.kt

@@ -75,7 +75,8 @@ val invalidUserScriptUrls = mutableListOf<String>()
 
 fun isUserScript(url: String?, path: String? = null): Boolean {
   if (url == null) return false
-  if (url.endsWith(".user.js")) {
+  if (url.endsWith(".user.js") ||
+      (Chrome.isEdge && url.endsWith(".js") && url.startsWith("file://"))) {
     if (invalidUserScriptUrls.contains(url)) return false
     invalidUserScriptDomains.forEach { if (url.startsWith("https://" + it) == true) return false }
     return true