Add contributing section to readme (#134)

* Add contributing section to readme

* Update README.md

README.md

@@ -70,6 +70,9 @@ Some of SCIP's plugins are imported to the rust interface as traits. Currently t
 
 To add a custom plugin to a SCIP `Model` instance, you should implement its trait and call the corresponding `include_{PLUGIN_NAME}` method. For examples on implementing the specific plugin trait you can check the tests in the corresponding files. 
 
+## Contibuting
+Thinking about contributing to _russcip_? First of all thank you! You can check our issues [page](https://github.com/scipopt/russcip/issues), there's a bunch of [_good_first_issues_](https://github.com/scipopt/russcip/issues?q=is%3Aissue+is%3Aopen+label%3A%22good+first+issue%22), or you can check our contribution [guide](CONTRIBUTING.md). If you'd like to contribute and unsure what to do, or thinking about a big feature and want to discuss if it makes sense and what is the best way to do it? you could open a new [issue](https://github.com/scipopt/russcip/issues/new/choose)/[discussion](https://github.com/scipopt/russcip/discussions/new/choose) or send me a quick email [@mmghannam](https://github.com/mmghannam).
+
 ## About SCIP
 
 SCIP is currently one of the fastest non-commercial solvers for mixed integer programming (MIP) and mixed integer nonlinear programming (MINLP). It is also a framework for constraint integer programming and branch-cut-and-price. It allows for total control of the solution process and the access of detailed information down to the guts of the solver.