- An improvement in the latest php-cs-fixer allows null coalescing rules to be applied more comprehensively.

- Update League/CommonMark to version 1.5.5
- Add new extensions to markdown.ini
- Update MarkdownFactory

- Includes upgrade to VuFindHttp 3.1.0.

- Resolves VUFIND-1284.

- Includes update to latest version of library.

- Eliminates deprecated Laminas\Console package in favor of Symfony\Console.
- Complete rewrite of all console utilities, including the addition of unit tests.

- Eliminate deprecated annotations and method calls.
- Add required return types to standard methods.
- Add php-cs-fixer rules to improve tests.
- Add .gitignore support for new test result cache.
- Fixed a few minor bugs/bad comments identified while upgrading.

* also see #21054
* install dependencies for codesniffer (difffilter) and php-cs-fixer via install-codestylechecker.sh
* remove difffilter package of coverage checker - reverts commit 8ae2e450.

* restore vanilla v5.1.0 composer configuration and dependencies
* drop composer platform php override to allow for dependencies requiring php > 7.0.8
* install and configure add composer merge plugin
* update npm-shrinkwrap.json
* add finc specific dependencies via custom composer file
* assure all symfony packages are locked to 3.4.*
* execute themes-copy script on composer install and update

* uncomments grunt compile error at themes/bootstrap3/scss/components/offcanvas .btn elements +28 for the moment
* updates composer.lock

* set new generator version at local/config/vufind/config.ini
* updates composer.lock