Add a CONTRIBUTING file

This file contains pointers to other important top-level resources,
and some info about acceptable licenses.  Also, add that info to
CodingStandards.md

CONTRIBUTING

@@ -0,0 +1,39 @@
+Contributing to Tor
+-------------------
+
+### Getting started
+
+Welcome!
+
+We have a bunch of documentation about how to develop Tor in the
+doc/HACKING/ directory.  We recommend that you start with
+doc/HACKING/README.1st.md , and then go from there.  It will tell
+you how to find your way around the source code, how to get
+involved with the Tor community, how to write patches, and much
+more!
+
+You don't have to be a C developer to help with Tor: have a look
+at https://www.torproject.org/getinvolved/volunteer.html.en !
+
+The Tor Project is committed to fostering a inclusive community
+where people feel safe to engage, share their points of view, and
+participate. For the latest version of our Code of Conduct, please
+see
+
+https://gitweb.torproject.org/community/policies.git/plain/code_of_conduct.txt
+
+
+
+### License issues
+
+Tor is distributed under the license terms in the LICENSE -- in
+brief, the "3-clause BSD license".  If you send us code to
+distribute with Tor, it needs to be code that we can distribute
+under those terms.  Please don't send us patches unless you agree
+to allow this.
+
+Some compatible licenses include:
+
+  - 3-clause BSD
+  - 2-clause BSD
+  - CC0 Public Domain Dedication

Makefile.am

@@ -38,6 +38,7 @@ include contrib/include.am
 
 EXTRA_DIST+= \
 	ChangeLog					\
+	CONTRIBUTING					\
 	INSTALL						\
 	LICENSE						\
 	Makefile.nmake					\

doc/HACKING/CodingStandards.md

@@ -42,6 +42,23 @@ If you have changed build system components:
    - For example, if you have changed Makefiles, autoconf files, or anything
      else that affects the build system.
 
+License issues
+==============
+
+Tor is distributed under the license terms in the LICENSE -- in
+brief, the "3-clause BSD license".  If you send us code to
+distribute with Tor, it needs to be code that we can distribute
+under those terms.  Please don't send us patches unless you agree
+to allow this.
+
+Some compatible licenses include:
+
+  - 3-clause BSD
+  - 2-clause BSD
+  - CC0 Public Domain Dedication
+
+
+
 How we use Git branches
 =======================
 
@@ -417,3 +434,4 @@ the functions that call your function rely on it doing something, then your
 function should mention that it does that something in the documentation.  If
 you rely on a function doing something beyond what is in its documentation,
 then you should watch out, or it might do something else later.
+