added more ruby like way to change a config object

Author: Asmod4n

README.md

@@ -42,6 +42,11 @@ config = Tls::Config.new # see https://github.com/Asmod4n/mruby-tls/blob/master/
 client = Tls::Client.new config
 ```
 
+You can later on change the configuration object
+```ruby
+client.config = config
+```
+
 Server example
 ```sh
 openssl ecparam -name secp256r1 -genkey -out private-key.pem

mrblib/context.rb

@@ -3,6 +3,7 @@ class Context
     attr_reader :config
     alias :recv :read
     alias :send :write
+    alias :config= :configure
 
     def self.new(config = nil)
       case config