While it is nice to have a working plugin example, it looks also a bit
overcomplicated to me. It is better for contributors, if they can find
things (like CLI argument parsing) in one (foreseeable) place and do
not have for things scattered over the whole project.

For plugin documentation we can use the sphinx docs. Or maybe provide
a sample plugin in tests.

This argument makes sense together with ``realdice`` randomsource
and tells how many sides the dice we use have. Six by default.

As we will start to do real things with the options passed in, we need
a real (options) dict also in other tests of `RealDiceRandomSource`.

The RealDiceRandomSource will support own commandline arguments. This
is handled by an own classmethod called `update_argparser` that is
called upon initialization of diceware.

If plugins want to work with their own commandline args, we allow
this by calling their `update_argparser` methods. This has to be a
classmethod, if it exists.

We got API changes, new options, etc. All this will make the
next release a minor one, not a pure bugfix.

Make sure we can use `-v` and `--verbose`.

In config files we normally lookup a ``[diceware]`` section.

For plugins, however, it might be helpful to be able to parse also
other sections. Together with the new `defaults_dict` argument
they could implement their own set of options more easily.

The `diceware.config.get_config_dict()` argument `path_list` was not
properly tested yet. Fix that.

We will not work on passed-in dicts but on copies thereof.

We can now give a custom dict to use for defaults.

This is the first step to make `get_config_dict()` usable also
for plugins.

It is probably not a bad idea to reflect default values in sample
config.

Oops, there were some remainings of an old edit that went unnoticed.

Especially changing the .ini-file parsing is more than a simple
bugfix.

Fix issue #23 
Thanks a lot, @dwcoder !

This commit fixes #23

Add the `string.strip()` function to the `get_config_dict()`, to remove
inverted commas around string values in the diceware.ini file.
The strip removes both `"` and `'`.
Add unit test to ensure the line:

    delimiter=" "

in the diceware.ini file is being parsed correctly as a space.

This helps to recognize options as such.

The removed vars were not really used in tests.

This way it is easier to check if any certain option is covered
already.

Try to cover all possibilities of `caps` related options when calling
`handle_options()`.

The modifications undone here, in
`test_handle_options_considers_configfile()` could have gone into an
own test. Each single test should only test a clear minimum of
things.

This specific test checked, whether configiles are considered at
all. It was not its purpose to examine correct interpretation of
keywords in the .ini-file; only to see whether these keyword values
can be changed at all.

If we wanted a complete and strict checking also of values, we had at
least to check all possible keywords, including 'randomsource' and
'wordlist'. Instead we only check a boolean, int, and string type
keyword.

Therefore the change to `test_handle_options_considers_configfile()`
should have gone to another test.

But then, the added testing is not neccessary. We had a test already
that should have checked the 'caps' value properly. This test was done
wrong before and is now done correctly, thanks to @dwcoder .

I therefore removed the added test functionality.