Update Cowlib to 2.2.1

Makefile

@@ -15,7 +15,7 @@ CT_OPTS += -ct_hooks cowboy_ct_hook [] # -boot start_sasl
 LOCAL_DEPS = crypto
 
 DEPS = cowlib ranch
-dep_cowlib = git https://github.com/ninenines/cowlib 2.2.0
+dep_cowlib = git https://github.com/ninenines/cowlib 2.2.1
 dep_ranch = git https://github.com/ninenines/ranch 1.4.0
 
 DOC_DEPS = asciideck

rebar.config

@@ -1,4 +1,4 @@
 {deps, [
-{cowlib,".*",{git,"https://github.com/ninenines/cowlib","2.2.0"}},{ranch,".*",{git,"https://github.com/ninenines/ranch","1.4.0"}}
+{cowlib,".*",{git,"https://github.com/ninenines/cowlib","2.2.1"}},{ranch,".*",{git,"https://github.com/ninenines/ranch","1.4.0"}}
 ]}.
 {erl_opts, [debug_info,warn_export_vars,warn_shadow_vars,warn_obsolete_guard,warn_missing_spec,warn_untyped_record]}.