minor #824 Add testing on PHP 7.1 (stof)

This PR was merged into the 1.4-dev branch.

Discussion
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Add testing on PHP 7.1

Commits
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17830e3 Add testing on PHP 7.1

bug #775 Fix the support of legacy scssphp formatters (stof)

This PR was merged into the 1.4-dev branch.

Discussion
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Fix the support of legacy scssphp formatters

Scssphp 0.5 removed the deprecated classes. But as there was no warning, people might not be aware that they were using a deprecated class.
This keeps support for the deprecated formatters in Assetic by matching them to their replacement, and warns the user about it.

Commits
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b422ec4 Update the scssphp tests to be less strict about formatting
d6641a5 Fix the support of legacy scssphp formatters

use * for consistency

Merge pull request #754 from stof/fix_twig_2

Fix the compatibility with Twig 2

Fixed CssCacheBustingFilter for data urls

Fix UglifyJs2 filter test

fixed test

Updated the changelog for 1.2.0

Removed the download of the cssembed jar as the url does not work any…

…more

updated changelog