Updated to PHP 7.4 and PHPUnit 9

3.0

Merge remote-tracking branch 'ariadne/master'

Minor changes in Exception names

Merge pull request #15 from poef/master

updated dependencies to make sure latest arc-base is used

Updated and new components

Updated

• arc/base
• arc/web
• arc/xml

new

• arc/html
• arc/prototype (experimental, api will change)

arc-arc: documentation and project info fixes

Fixed license version