added language strings for #2601

public/language/en_GB/category.json

@@ -1,5 +1,6 @@
 {
 	"new_topic_button": "New Topic",
+	"guest-login-post": "Log in to post",
 	"no_topics": "<strong>There are no topics in this category.</strong><br />Why don't you try posting one?",
 
 	"browsing": "browsing",

public/language/en_GB/topic.json

@@ -15,6 +15,7 @@
 	"notify_me": "Be notified of new replies in this topic",
 	"quote": "Quote",
 	"reply": "Reply",
+	"guest-login-reply": "Log in to reply",
 	"edit": "Edit",
 	"delete": "Delete",
 	"purge": "Purge",