Updated robot framework assistan plugin compatability

The version 2.0.0 will be compatinle only with
Sublime Text 3 and later versions are
compatible with Sublime 2&3

repository/r.json

@@ -1070,7 +1070,11 @@
 			"releases": [
 				{
 					"sublime_text": "*",
-					"branch": "master"
+					"tags": "st2-"
+				},
+				{
+					"sublime_text": ">=3000",
+					"tags": "st3-"
 				}
 			]
 		},