Fix intent/follow URL redirect

Fixes #629

src/routes/timeline.nim

@@ -105,6 +105,12 @@ proc createTimelineRouter*(cfg: Config) =
     get "/intent/user":
       respUserId()
 
+    get "/intent/follow/?":
+      let username = request.params.getOrDefault("screen_name")
+      if username.len == 0:
+        resp Http400, showError("Missing screen_name parameter", cfg)
+      redirect("/" & username)
+
     get "/@name/?@tab?/?":
       cond '.' notin @"name"
       cond @"name" notin ["pic", "gif", "video", "search", "settings", "login", "intent", "i"]

src/routes/unsupported.nim

@@ -17,7 +17,7 @@ proc createUnsupportedRouter*(cfg: Config) =
     get "/@name/lists/?": feature()
 
     get "/intent/?@i?": 
-      cond @"i" notin ["user"]
+      cond @"i" notin ["user", "follow"]
       feature()
 
     get "/i/@i?/?@j?":