contributing: add information for caine bot

CONTRIBUTING.md

@@ -429,3 +429,52 @@ or else the discussion will continue. Simple majority wins.
 
 Note that changes to TC membership require unanimous consensus.  See
 "Membership" above.
+
+## Caine's requirements
+
+Hello!
+
+I am pleased to see your valuable contribution to this project. Would you
+please mind answering a couple of questions to help me classify this submission
+and/or gather required information for the core team members?
+
+### Questions:
+
+* _Issue-only_ Does this issue happen in core, or in some user-space
+  module from npm or other source? Please ensure that the test case
+  that reproduces this problem is not using any external dependencies.
+  If the error is not reproducible with just core modules - it is most
+  likely not a io.js problem. _Expected: `yes`_
+* Which part of core do you think it might be related to?
+  _One of: `tls, crypto, buffer, http, https, assert, util, streams,
+  smalloc, cluster, child_process, dgram, c++, docs, other`_ (_label_)
+* Which versions of io.js do you think are affected by this?
+  _One of: `v0.10, v0.12, v1.0.0`_ (_label_)
+* _PR-only_ Does `make test` pass after applying this Pull Request.
+  _Expected: `yes`_
+* _PR-only_ Is the commit message properly formatted? (See
+  CONTRIBUTING.md for more information)
+  _Expected: `yes`_
+
+Please provide the answers in an ordered list like this:
+
+1. Answer for the first question
+2. Answer for the second question
+3. ...
+
+Note that I am just a bot with a limited human-reply parsing abilities,
+so please be very careful with numbers and don't skip the questions!
+
+_In case of success I will say:_ `...summoning the core team devs!`.
+
+_In case of validation problem I will say:_ `Sorry, but something is not right
+here:`.
+
+Truly yours,
+Caine.
+
+### Responsibilities
+
+* indutny: crypto, tls, https, child_process, c++
+* trevnorris: buffer, http, https, smalloc
+* bnoordhuis: http, cluster, child_process, dgram