Fix typo: 'Currrently' -> 'Currently' in router README (#243)

Author: anuj-pal27

lib/rage/router/README.md

@@ -1,6 +1,6 @@
 This is an almost complete rewrite of https://github.com/delvedor/find-my-way.
 
-Currrently, the only constraint supported is the `host` constraint. Regexp constraints are likely to be added. Custom/lambda constraints are unlikely to be added.
+Currently, the only constraint supported is the `host` constraint. Regexp constraints are likely to be added. Custom/lambda constraints are unlikely to be added.
 
 Compared to the Rails router, the most notable difference except constraints is that a wildcard segment can only be in the last section of the path and cannot be named.