Partially complete Sphinx documentation

Sphinx documentation with empty place holder for tutorial. Migration of
README for guide. And API documentation for begin.start decorator.

docs/api.rst

@@ -0,0 +1,66 @@
+==============
+The begins API
+==============
+
+.. module:: begin
+    :noindex:
+
+The :mod:`begin` module provides the bulk of *begins* decorator API.
+
+.. decorator:: start(auto_convert=False, cmd_delim=None, short_args=True, lexical_order=False, env_prefix=None, config_file=None, config_section=None, sub_group=None, collector=None)
+
+   Annotates the decorated function as the programs main function. If the
+   module is run, the function will be automatically called after processing
+   options from the command line.
+
+   If *auto_convert* is ``True`` the decorated function will also be decorated
+   by :func:`begin.convert` with automatic type conversion enabled.
+
+   If *cmd_delim* is provided, it will be used as a separator on the command
+   line between multiple sub-commands that are to be called in sequence.
+
+   If *short_args* is ``False`` (default is ``True``) the use of short, single
+   character options on the command line is suppressed.
+
+   If *lexical_order* is ``True`` (default is ``False``) command line options
+   in help output will be in alphabetical order rather than the order in which
+   they appear in the function signature.
+
+   If *env_prefix* is provided, the use of environment variables for changing
+   the default value of command line options is enabled. The value of
+   *env_prefix* is used as a prefix in front of environment variables. An empty
+   string my be provided to indicate no prefix but still enable the use of
+   environment variables.
+
+   If *config_file* is provided, it's the name of a file in the current and
+   user's home directory from which configuration options will be loaded to
+   change the default values of command line options.
+
+   If *config_section* is provided it overrides the decorated function name as
+   the configuration file section from which to load command line option
+   defaults.
+
+   The *sub_group* changes the collector name used to load sub-commands from.
+   The *sub_group* name must match the *group* name provdided to the
+   :func:`begin.subcommand` decorator.
+
+   The *collector* allows a :class:`begin.subcommand.Collector` of sub-commands
+   to be provided instead of a named collector.
+
+Sub-commands
+============
+
+.. decorator:: subcommand(name=None, group=None, collector=None)
+
+   TODO
+
+TODO
+
+Type conversion
+===============
+
+.. decorator:: convert(**kwargs)
+
+   TODO
+
+.. module:: begin.utils