This commit refactors the code that handles exporting e-mails opens and
clicks when generating the personal data file to use Doctrine instead of
Paris. I opted to do this in this task as opens and clicks code share
some functionality, and I didn't want to add more code that relies on
Paris, as we are eventually going to remove it.
[MAILPOET-3738]
This commit adds stats about email opens data to the personal data
exported by WP.
To do this, I refactored the code that adds email clicks stats to use
base abstract class with functionality that is shared between both
exporters.
[MAILPOET-3738]
This commit includes information about the user agent used when clicking
links in e-mails to the data that MailPoet exports when the WP tool
"Export Personal Data" is used.
When information about the user agent is not available, the string
'Unknown' is displayed instead.
This information is available under the section "MailPoet Emails
Clicks".
[MAILPOET-3738]
