Update signature to match docs.

[jean]

In https://github.com/bluedynamics/souper.plone/blob/master/README.rst we read >>> soup = get_soup(context, 'my_soup_id') and in https://github.com/bluedynamics/souper.plone/blob/master/src/souper/plone/locator.rst we read >>> get_soup(plone, 'mysoup') (sometimes).

[rnixx]

hi, thx for the pull request. we should do the other way around, update the docs instead of changing the function signature, the package is already used at several places and it's not worth to break them.

[jean]

Hi rnixx, thanks for being patient. Yes, normally I would update the docs, but the signature seems back to front to me, the docs are divided on the topic, and I've added a BBB fallback with deprecation message so old code shouldn't break.

That said, I would quite understand if you decline the get_soup change.

daf5708 is a simple fix though.

[jensens]

b05e0db fixes daf5708 - but we keep signature, its all in production already and soupid is more important than context, well even if its the other way around this way than most plone calls (getToolByName, ...) - but this is also used outside of zope/plone (pyramid, ..., name it)