update contribution guidelines

CONTRIBUTING.md

@@ -1,4 +1,4 @@
 # Contributing
-Your feedback and contributions are welcome. If you have a suggestion, please raise an issue. Prior to that, please search through the issues first in case your suggestion has been made already. If you decide to work on an issue, please announce on the issue thread that you will work on it.
+Your feedback and contributions are welcome. If you have a suggestion, please raise an issue. Prior to that, please search through the issues first in case your suggestion has been made already. If you decide to work on an issue, or feel like taking initiative and contributing anything at all, feel free to create a pull request and I will get back to you shortly.
 
 Pull requests should provide some basic context and link the relevant issue. Here is an [example pull request](https://github.com/a-synchronous/rubico/pull/12). If you are interested in contributing, the [help wanted](https://github.com/a-synchronous/rubico/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) tag is a good place to start.

README.md

@@ -171,7 +171,7 @@ For even more advanced functions, please visit `rubico/x`. You can find the full
  * [SurviveJS Rubico Interview](https://survivejs.com/blog/rubico-interview/)
 
 # Contributing
-Your feedback and contributions are welcome. If you have a suggestion, please raise an issue. Prior to that, please search through the issues first in case your suggestion has been made already. If you decide to work on an issue, please announce on the issue thread that you will work on it.
+Your feedback and contributions are welcome. If you have a suggestion, please raise an issue. Prior to that, please search through the issues first in case your suggestion has been made already. If you decide to work on an issue, or feel like taking initiative and contributing anything at all, feel free to create a pull request and I will get back to you shortly.
 
 Pull requests should provide some basic context and link the relevant issue. Here is an [example pull request](https://github.com/a-synchronous/rubico/pull/12). If you are interested in contributing, the [help wanted](https://github.com/a-synchronous/rubico/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) tag is a good place to start.