Fix typo

README.md

@@ -18,7 +18,7 @@ Project Status and Versioning
 -----------------------------
 
  *  Development stage is something between "experimental" and "alpha",
-    that is lot of tests are yet to be written and only real user is
+    that is, lot of tests are yet to be written and only real user is
     its own author.
 
  *  API (commands, options...) may be changed/removed as needed.