[docs] First documentation on settings and environment variables.

docs/reference/index.rst

@@ -1,10 +1,14 @@
 References
 ==========
 
+Reference documents of all stable APIs and modules. If something is not here, please be careful about using it as it
+means that the api is not yet 1.0-proof.
+
 .. toctree::
     :maxdepth: 4
 
     api
     api_config
     commands
+    settings
     examples

docs/reference/settings.rst

@@ -0,0 +1,56 @@
+Settings & Environment
+======================
+
+.. module:: bonobo.settings
+
+All settings that you can find in the :module:`bonobo.settings` module.
+
+Debug
+:::::
+
+:Purpose: Sets the debug mode, which is more verbose. Loglevel will be lowered to DEBUG instead of INFO.
+:Environment: `DEBUG`
+:Setting: `bonobo.settings.DEBUG`
+:Default: `False`
+
+Profile
+:::::::
+
+:Purpose: Sets profiling, which adds memory/cpu usage output. Not yet fully implemented. It is expected that setting
+          this to true will have a non-neglictible performance impact.
+:Environment: `PROFILE`
+:Setting: `bonobo.settings.PROFILE`
+:Default: `False`
+
+Quiet
+:::::
+
+:Purpose: Sets the quiet mode, which ask any output to be computer parsable. Formating will be removed, but it will
+          allow to use unix pipes, etc. Not yet fully implemented, few transformations already use it. Probably, it
+          should be the default on non-interactive terminals.
+:Environment: `QUIET`
+:Setting: `bonobo.settings.QUIET`
+:Default: `False`
+
+Logging Level
+:::::::::::::
+
+:Purpose: Sets the python minimum logging level.
+:Environment: `LOGGING_LEVEL`
+:Setting: `bonobo.settings.LOGGING_LEVEL`
+:Default: `DEBUG` if DEBUG is False, otherwise `INFO`
+:Values: `CRITICAL`, `FATAL`, `ERROR`, `WARNING`, `INFO`, `DEBUG`, `NOTSET`
+
+I/O Format
+::::::::::
+
+:Purpose: Sets default input/output format for builtin transformations. It can be overriden on each node. The `kwargs`
+          value means that each node will try to read its input from keywords arguments (and write similar formated
+          output), while `arg0` means it will try to read its input from the first positional argument (and write
+          similar formated output).
+:Environment: `IOFORMAT`
+:Setting: `bonobo.settings.IOFORMAT`
+:Default: `kwargs`
+:Values: `kwargs`, `arg0`
+
+