[minor] Allow databasejoin as primary key

[Sophist-UK]

See first commit for functional change. This adds databasejoin to the list of plugins supported for primary key so that databasejoin elements appear in the selection dropdown box.

Second commit is purely cosmetic.

[cheesegrits]

Unfortunately, PHP Storm has fairly limited support for XML code formatting, which is why XML's are formatted like they are, and are going to have to stay that way. If you start reformatting them, next I edit, it's all going to change back. So please don't reformat, and try and keep formatting to the way it is - so first attribute on the same line, and subsequent ones alligned with that.

[cheesegrits]

(I'm trying to find out from some of the core J! devs how the format their XML - I knwo most of them use PHP Storm now, but I have no cue how they achieve the formatting they do on their XML's)

[Sophist-UK]

My formatting is to Joomla standard - so they must have a way to format XML to their standard using Storm.

[cheesegrits]

Yes, I know your formatting is J! standard. I already said that. And they may have found a way to do it in PHP Storm, but I don't, and trust me, I have tried, to the point of submitting bug reports to JetBrains. So XML format is going to have to stay as-is until I figure it out.

Here's what happens, regardless of my XML code formatting settings ...

https://www.screencast.com/t/FBAuT1xF

... so it automatically tabs the first attribute out past the end of the field name when I enter, and if I try and just backspace, it moves it back to the previous line. So the only way to do it is to manually hit enter, manually select one tab character, and manually delete it, and this has to be done for every attribute. If I use 'reformat', it'll always put it back to the PHP Storm way of having the first attribute on the same line, then subsequent lines either lined up with it, or tabbed further out.

And I simply don't have time to manually reformat every attribute line. And I don't want a mix of formats, as that just confuses my mental eye / brain muscle memory. So until PHP Storm can reformat to that style ... XML is staying the way it is.

So please revert those XML style changes so I can merge this one.

[Sophist-UK]

I am not disagreeing with you. Quite the opposite.

I assume you have seen https://github.com/betweenbrain/phpstorm-joomla-code-style ?