PHP 7 compatibility

[schmengler]

The following issue has been found in src/KJ/Magento/Util/Comparison/Filter/Null.php:

'null' is a reserved keyword as of PHP version 7.0 and should not be used to name a class, interface or trait or as part of a namespace

[kalenjordan]

Doh! Got it thanks. Man I haven't worked on this for so long....I wonder if someone might want to PR the fix or maybe even take over the repo...?

[sreichel]

I wonder if someone might want to PR the fix or maybe even take over the repo...?

Guess it will need an update for upcomming magerun v3 release ....

I'd take care for the repo ....