Fixes #120 - Add CONTRIBUTING (#121)

CONTRIBUTING.md

@@ -0,0 +1,73 @@
+# Contributing
+
+How can I contribute to Piranha? Well it all depends on the level of 
+involvement you are aiming for. The following comes to mind:
+
+1. Write blog entries with example applications
+2. File issues for bugs you encounter.
+3. Answer questions that people file at the issue tracker.
+4. Fork the repository and issue pull requests.
+
+Which ever level you pick we welcome you!
+
+## Important notice
+
+Note if you file issues, answer questions and/or issue pull requests you agree
+that those contributions will be owned by Manorrock.com and that Manorrock.com 
+can use those contributions in any manner Manorrock.com so desires.
+
+## Building and testing Piranha locally
+
+### Building Piranha and running the tests
+
+```
+mvn clean install
+```
+
+If you do not want the tests to run use:
+
+```
+mvn -DskipTests clean install 
+```
+
+### Running a singular test
+
+To run a singular test pass in `-Dtest=expression`, see the `surefire` plugin
+documentation for more information.
+
+### Running our more complex tests
+
+Our more complex tests are in the `test` profile which we do not release as part
+of a release because these modules only test functionality.
+
+You can run our more complex tests using:
+
+```
+mvn -P test clean install
+```
+
+### Run the external tests (including TCKs)
+
+To run all the external tests use:
+
+```
+mvn -P external clean install
+```
+
+Or go into the directory of the external test you want to run and use:
+
+```
+mvn clean install
+```
+
+For the Servlet TCK if you want to run a singular test use 
+`-Drun.test=expression`. See the example below.
+
+```
+mvn -Drun.test=com/sun/ts/tests/servlet/spec/errorpage/URLClient.java#servletToDifferentErrorPagesTest verify
+```
+
+## Problems
+
+Support for Java modules has a feature gap in Eclipse and as such a workaround
+needs to be employed to make it work properly (June 2021).

README.md

@@ -1,3 +1,7 @@
 # Piranha Start
 
 See for the running version of Piranha Start at http://start.piranha.cloud/
+
+## How do I contribute?
+
+See [Contributing](CONTRIBUTING.md)