Updates contribution guide

CONTRIBUTING.md

@@ -1,10 +1,30 @@
 # Contributing to Logarion
 
-There are three layers: the file format, the repository system, and the outlets.
+Logarions primary aim is to create a note system, which doesn't waste resources.
+The secondary aim is to provide an exemplary OCaml project to demonstrate and promote the language (as it happens with many other "Blogging" systems written in other languages).
 
-    ymd.ml <--> logarion.ml <--> intermediate formats <--> programs
+As part of the secondary aim, the source code needs to written in a way that encourages the language's adoption and the participation to the OCaml developer community.
 
-Design principles:
+## Starting with OCaml
+
+_"OCaml is an industrial strength programming language supporting functional, imperative and object-oriented styles"_ -- https://ocaml.org/
+
+OCaml simply rocks.
+
+If you are unfamiliar with OCaml, consider starting with these resources:
+
+- Install OCaml: https://ocaml.org/docs/install.html
+- Read about OCaml: https://ocaml.org/learn/books.html
+- Ask questions & join the community:
+  - Mailing lists: https://ocaml.org/community/
+  - IRC: irc://irc.freenode.net/#ocaml (Web client: https://riot.im/app/#/room/#freenode_#ocaml:matrix.org )
+  - Reddit: http://www.reddit.com/r/ocaml/
+  - Discourse: https://discuss.ocaml.org/
+  - .. other: https://ocaml.org/community/
+
+## Design principles
+
+[Unix phisophy](https://en.wikipedia.org/wiki/Unix_philosophy#Do_One_Thing_and_Do_It_Well)
 
 1. System simplicity & interoperability.
 2. Output quality.
@@ -12,10 +32,18 @@ Design principles:
 
 ## Source
 
+### Layers
+
+There are three layers:
+
+- notes 
+- archive 
+- interfaces & intermediate formats
+
 ### Core
 
-- `logarion.ml`: repository related functions (listing, adding/removing, etc).
-- `ymd.ml`: parsing from and to YMD files.
+- `logarion.ml`: repository related functions (listing, adding/removing, etc). ([src/logarion.ml](https://gitlab.com/orbifx/logarion/blob/master/src/logarion.ml))
+- `note.ml`: parsing from and to note files. ([src/note.ml](https://gitlab.com/orbifx/logarion/blob/master/src/note.ml))
 
 ### Intermediate formats