Support PHP 7.1 and PHP 7.2

[bobbingwide]

oik-bwtrace needs to support being run under PHP 7.1 and PHP 7.2

Known changes

• We should update the End of Life table to add PHP 7.1's EOL - 2019/12/01
• We should add PHP 7.2's EOL - 2020/11/30

See http://php.net/supported-versions.php

[bobbingwide]

Problems detected with PHP 7.2 Warning: count(): Parameter must be an array or an object that implements Countable in

• oik-bwtrace\includes\bwtrace.php on line 350
• oik-bwtrace\includes\oik-action-counts on line 223
• oik-bwtrace\includes\bwtrace.php on line 117

[bobbingwide]

We'll also use this issue to develop any PHPUnit tests that aren't directly associated with other issues.