Adding detailed contributing information and census.

Author: thomaswue

CENSUS.md

@@ -0,0 +1,21 @@
+The project's census with roles as defined in (CONTRIBUTING.md)[CONTRIBUTING.md).
+
+### Project Leads
+* Developer Advocate Lead
+  * [Alina Yurenko](https://github.com/alina-yur)
+* Security Group Lead
+  * [Matthias Neugschwandtner](https://github.com/matneu)
+* Project Lead
+  * [Thomas Wuerthinger](https://github.com/thomaswue)
+
+### Technical Area Leads
+* Compiler
+  * [Doug Simon](https://github.com/dougxc)
+* Native Image
+  * [Christian Wimmer](https://github.com/christianwimmer) 
+* Truffle
+  * [Christian Humer](https://github.com/chumer)
+* Espresso
+  * [Alfonso Peterssen](https://github.com/mukel)
+
+### Committers

CONTRIBUTING.md

@@ -1,7 +1,57 @@
+# For Contributors
+
 GraalVM welcomes contributors to the core platform and projects that extend that
 platform. There have been significant contributions from both industry
 and academia so far and we thank you for considering to contribute your changes!
 
+### How to Contribute
+
 - Learn [how to become a GraalVM contributor](https://www.graalvm.org/community/contributors/).
   - Check individual README.md and CONTRIBUTING.md files in the subprojects to learn how to build and import them into your IDE (for example, [the compiler README.md](compiler/README.md))
 - Subscribe and post to [[email protected]](https://oss.oracle.com/mailman/listinfo/graalvm-dev) for questions related to working with the sources or extending the GraalVM ecosystem by creating new languages, tools, or embeddings.
+
+### Contributor Roles
+
+There are different roles for contributors of the project. Find a list of current contributors in [CENSUS.md](CENSUS.md).
+
+* Committer
+  * Has Signed the [Oracle Contributor Agreement](https://oca.opensource.oracle.com/), which is a prerequisite for contributing to the project
+  * At least one pull request authored by the individual has been merged
+
+* Code Owner
+  * Source code directories contain an OWNERS.toml metadata file to define one or more Code Owners.
+  * If there is no such file, the property of the parent directory is inherited.
+  * A change to the source code must be approved by at least one of the Code Owners.
+  * Large modifications should be discussed with the Technical Area Lead for architectural design before a pull request is created.
+
+* Technical Area Lead
+  * Code Owner with primary responsibility for architecture and design of a specific area
+  * Has the ability to veto changes in his area on technical grounds
+
+* Security Lead
+  * Organizes the vulnerability group for sharing security patches
+  * Reviews pull requests for aspects relevant for security
+  * Primary point of contact in case of discussing a potential security vulnerability
+
+* Developer Advocacy Lead
+  * Manages interactions within the GraalVM Community
+  * Runs the Advisory Board
+  * Primary point of contact for enquiries related to the GraalVM community or community support
+
+* Project Lead
+  * Defines an overall technical direction
+  * Mediates disputes over code ownership
+  * Appoints the Security Lead, Developer Advocacy Lead, and Technical Area Leads
+  * Appointed by Oracle
+
+### Backports
+
+For versions of GraalVM with ongoing community maintenance and backport support, a Lead Maintainer is chosen among the project contributors. That lead maintainer is responsible for managing the corresponding community backport repository. See [here](https://github.com/oracle/graal/issues/8935) an example of a call for a lead maintainer.
+
+### Advisory Board
+
+Apart from source code contributors to the project, there is also a role for advisory board members that discuss project matters and direction as well as drive awareness and adoption of GraalVM technology. Find a description of the advisory board and its current members [here](https://www.graalvm.org/community/advisory-board/).
+
+### Security
+
+Entities interested in sharing reports of vulnerabilities and collaborate on security fixes should contact the Security Lead.