[Develop] Add travis script

[jrfnl]

Needs IRL test

Also:

• Rename phpcs.xml to ruleset.xml so PHPStorm can pick it up
• Fix all but one remaining code style issue
• only show var_dump() on error when WP_DEBUG is set to true
• Remove unnecessary concatenation in echo statements for lower memory usage

[GaryJones]

Doesn't Travis only support 5.3 min now?

What about 5.3, 5.4, 5.5? Occasionally something breaks there, and currently we would only know that it passed the low PHP level, but failed at 5.6.

[jrfnl]

I'm pretty sure they reverted the removal of PHP 5.2 (under pressure of the WP community).

As we're currently only doing a lint and phpcs, running it on more versions would be wasting resources as the results won't change. If it breaks on either of those two versions, we need to look at the code, everything in between is caught by this.

Once we have unit tests, we should start running it on more versions, though still only lint and phpcs on highest and lowest.

[GaryJones]

I think the addition of .travis.yml, the change in phpcs config file, and the code fixes should all have been in different branches. I like the code changes, but have questions about the other two.

[jrfnl]

I think the addition of .travis.yml, the change in phpcs config file, and the code fixes should all have been in different branches. I like the code changes, but have questions about the other two.

I'll keep that in mind for that future.

In this case I think they are related (except for the concatenation commit which was just extra). Adding the travis script which runs phpcs and will fail straight away on errors would mean that the travis config could not be merged. (providing we'll hook it in now to test this PR before merge)

[jrfnl]

Updated PR

[jrfnl]

@GaryJones shouldn't we hook travis in first to test this PR ?

[GaryJones]

It will get tested once we are hooked up - we can adjust it from there.