Updated phpmailer to 5.2.2

Should resolve:
https://snowy-evening.com/botsko/dhmc/209/
https://snowy-evening.com/botsko/dhmc/210/

is_resource is checks before feof and fgets

Possibly helps:
https://snowy-evening.com/botsko/dhmc/215/
https://snowy-evening.com/botsko/dhmc/182/

several changes to MIME handling and Base64 encoding