Hardcoded scenarios

[greg-1-anderson]

This is an alternative to #84. Merge one or the other, but not both.

Advantages to this PR:

• No 3rd party library required
• No need to commit a scenarios directory

Disadvantages to this PR:

• More complex .travis.yml
• Lose composer scenario phpunit4 command, so it's harder to do local tests on other scenarios
• Would get unmanageable with more scenarios / more package variations per scenario

For this project, going with this PR would be fine, I think, if you wanted to avoid the scenarios folder.

[greg-1-anderson]

Tests are not running because I don't have the syntax right in the "install" section. I'll have to fix that later; this PR shows the general idea though.

[greg-1-anderson]

This PR sort of illustrates why I wrote composer-test-scenarios. I used to make my .travis.yml files like this, but fiddling with the bash expressions in the travis config file directly is harder to read and error-prone. Factoring these scripts -- even as short as they are -- out into a separate library means that it is not necessary to do this for each new project.

I therefore recommend sticking with #84, although this variant is perfectly acceptable if you want to get rid of the sceanarios folder.

[webflo]

Closed in favour of https://github.com/drupal-composer/drupal-scaffold/pull/84