Updated README with some basic development guidelines

README

@@ -50,6 +50,89 @@ repository is welcome and the right thing to do :)
 At the time of writing there's no API reference or documentation. The code does
 have a lot of comments though (and getting better all the time).
 
+Contributing to DFHack
+----------------------
+
+Several things should be kept in mind when contributing to DFHack.
+
+Keep the same coding style. DFhack uses ANSI formatting and four spaces as
+indentation. Line endings are UNIX. Code not following this won't make
+me happy, because I'll have to fix it.
+
+* How to get new code into DFHack  
+You can send patches or make a clone of the github repo and ask me on the
+IRC channel to pull your code in. I'll review it and see if there are any
+problems. I'll fix them if they are minor.
+
+Fixes are higher in priority. If you want to work on something, but don't
+know what, check out http://github.com/peterix/dfhack/issues -- this is also
+the place for new ideas.
+
+* Layout for tools
+dfhack/     The folder for core dfhack. The libraries are in there.
+tools/      This is used for stable and supported tools. These get distributed
+            in binary releases and should be tested.
+examples/   This folder has some examples that show how to use certain parts
+            of dfhack.
+playground/ And finally, here should be placed any quick hacks and testing
+            tools.
+
+Don't put untested or experimental things in tools/.
+
+* Layout for core dfhack
+dfhack/                -- the main library lives here
+dfhack/include         -- header files for the main library belong here
+dfhack/modules         -- source of the client modules goes here
+dfhack/include/modules -- headers for client modules
+dfhack/shm             -- the server part along with its modules
+dfhack/python          -- folder for the pytthon bindings
+dfhack/depends         -- dependencies. an XML parser, an MD5 implementation
+                          and terminal arguments parser.
+
+* Modules - what are they?
+DFHack uses modules to partition sets of features into manageable chunks.
+A module can have both client and server side.
+
+Client side is the part that goes into the main library and is generally
+written in C++. It is exposed to the users of DFHack.
+
+Server side is used inside DF and serves to accelerate the client modules.
+This is written mostly in C style.
+
+There's a Core module that shouldn't be changed, because it defines
+the basic commands like reading and writing raw data. The client parts
+for the Core module are the various implementations of the Process
+interface.
+
+A good example of a module is Maps. Named the same in both client and
+server, it allows accelerating the reading of map blocks.
+
+Communication between modules happens by using shared memory. This is
+pretty fast, but needs quite a bit of care to not break. 
+
+* Dependencies
+
+If you want to add dependencies, think twice about it. All dependencies
+for core dfhack should be either public domain or require attribution
+at most.
+Dependencies for tools can be either that, or any Free Software licenses.
+
+* Current internal dependencies
+
+tinyxml: used by core dfhack to read offset definitions from Memory.xml
+md5:     an implementation of the MD5 hash algorithm. Used for identifying
+         DF binaries on Linux.
+argstream: Allows reading terminal application arguments. GPL!
+
+* Current external dependencies
+
+wide-character ncurses: used for the veinlook tool on Linux.
+python 2.6:             required for building and using the python bindings.
+
+* Build-time dependencies
+
+cmake: you need cmake to generate the build system and some configuration
+       headers
 
 Tools
 -----