fixes #19881 and #19899 - added maxlen to file_get_content for JS and CS...

This would fix fixes #19881 (Maximum number of errors) and #19899 (Exclude files like compressed JS based on e.g. size)

file_get_content php function has this parameter which allow us to set a maximum length of data read. We can use this to make phpcs stop when it reaches some limit.

I've found 100000 to be a good value but we can use another one or even create an argument like 
"... --limit=low,normal,high"