Add actual file moving

Prevent installation of PHP7.3 polyfill

Remove unnecessary command

Fix case insensitive string comparison

Allow class_exists(..., false) to inform class-string type

Remove TSqlSelectString and related dependency

Fix vimeo#1628 - improve behaviour of unset in loops

Fix vimeo#1616 - allow Psalm to output checkstyle format

Allow MixedArrayTypeCoercion to be properly suppressed by default

Fix checks for parent method implementers