Accept a Symbol in BSD::Control.feature!

README.md

@@ -33,7 +33,7 @@ The example enables the mprotect feature for the emacs binary:
 # As a root account
 require 'hbsdctl'
 BSD::Control
-  .feature!("mprotect")
+  .feature!(:mprotect)
   .enable!("/usr/local/bin/emacs")
 ```
 

lib/bsd/control.rb

@@ -23,7 +23,7 @@ module BSD::Control
   # @return [BSD::Control::Feature]
   #  Returns an instance of BSD::Control::Feature.
   def self.feature!(name)
-    feature = Feature.available.find { _1.name == name }
+    feature = Feature.available.find { _1.name == name.to_s }
     feature ? feature : raise(Error, "feature '#{name}' wasn't found")
   end