New features

[5e0b275] Use the String component (@javiereguiluz) [2227440] Use new functional test specific assertions (@voronkovich) [177b652] Use short syntax for routes HTTP methods (@voronkovich) [e01aebb] Replaced SwiftMailer by Symfony Mailer (@javiereguiluz) [17bf17b] Made blog post titles unique (@javiereguiluz) [5eae5f2] Validate Composer files while TravisCI build (@voronkovich) [d94fcc8] Required symfony/apache-pack package (@bocharsky-bw) [e2944ce] Updated tgalopin/html-sanitizer to remove Intl extension requirement (@tgalopin)

Bug fixes

[4e1522b] Fixed broken links (@voronkovich) [7cbada1] Made tests compatible with PHPUnit 8 (@voronkovich) [4966423] Removed "symfony/polyfill-php72" from the dependencies (@rosier) [3abd67a] Use a more friendly message about hardcoding user details (@pierredup) [4016b3c] Add a translation for a message about slug uniqueness (@voronkovich) [3b68b6d] Updated Ukrainian translation (@bocharsky-bw) [0583b4d] Updated Russian translation (@Coderberg)