Upgrade travis to trusty environment

[mneudert]

work in progress

Removes any direct requirements to the "sudo: enabled" travis infrastructure and migrates to "dist: trusty".

[ref matomo-org/matomo#11986]

[mattab]

Hi @mneudert - thanks for creating this PR!
How is the progress going so far?
Let us know when we can review/test this further and hopefully merge it 👍

[mneudert]

With the LoginLdap-PR merged only the SystemTests (see last build here) and the UITests need to be checked/adapted to run using the new dist: trusty setting. Probably needs some cleanup afterwards or modifications for plugin tests but it is looking quite good at the moment 🙂

[mattab]

@mneudert Do you know if MySQL runs off the RAM in trusty?
(I remember this was a reason we couldn't use the "Sudo less" setup before, because MySQL and our build was too slow when not running off the RAM. )

[mneudert]

The SystemTests and IntegrationTests (and therefore AllTests) will keep using sudo: required even after the switch to trusty. Keeping the sudo requirement allows keeping the ramdisk available because without it the time required for aforementioned suites raises from 25 minutes to 45 minutes.

[mneudert]

The tests are now mostly working so I would say this is ready for a quick review. Changes currently only target core testing with the intent to not break any plugins and switch them over in a second pass. With one or two additional steps of cleanup and perhaps extension/restructuring.

Caveats:

• Occasionaly a test from the SystemTests suite seems to break with a change in the order of the results checked. This might be a result of the default MySQL version change from 5.5 to 5.6 or completely unrelated.
• The UITests suite is partially broken, perhaps due to some change in gd (FreeType Support changed from true to false). Ignoring the minor changes in font rendering (resulting in something like a 3px difference failure) some tests seem to not generate any image at all.

Next step is to ensure I have not broken any plugin testing environment...