Some version fixes for 2.2

[wouterj]

Q	A
Doc fix?	yes
New docs?	no
Applies to	2.2+
Fixed tickets	-

[xabbuh]

2.3 is also released, should be reflected here, I guess

[wouterj]

No, that should be reflected on the 2.3 branch (did that in #2690 )

[weaverryan]

@wouterj - can we do anything with this PR? Some of these changes were made in #2690 and there are problems with some others. Specifically, for the URL changes, we just can't do this (https://github.com/symfony/symfony-docs/pull/2692/files#pullrequestreviewcomment-4954866). If we change the 2.2 URLs all to 2.2, then when we merge to 2.3, we'll need to then re-fix all of the URLs to be 2.3 there. Then again when we merge to master :). Of course, when 2.4 is made into a branch, we'll change all of its URLs to be 2.4, but when we merge back up to master, we'll once again have a mess. I think the only solution is to properly fix this with a Sphinx extension, which shouldn't be too hard, we just need to do it :).

So, can we close this PR?

[wouterj]

@weaverryan instead of creating a sphinx extension, we can use the build-in |version| substitution. But this requires to set the correct version option in the config.

@fabpot is the version option changed when rendering the versions? In other words, are we able to use |version| in the docs?

[weaverryan]

@wouterj I thought the same thing, but I don't think it's possible. If you put |version| somewhere in the middle of your document, it works great. But as soon as you have it in the URL of a link, it's not parsed. It seems the URL for a link is read completely statically - no expressions are parsed. For example:

.. _`Twig Bridge`: https://github.com/symfony/symfony/tree/|version|/src/Symfony/Bridge/Twig

If you can find a way around this, let me know!