Plugin to display lint errors on project build

[baptistecs]

This method allows to:

• Use SwiftFormat as a linter, to prevent project developers to build non formatted code.
• Keep the ENABLE_USER_SCRIPT_SANDBOXING (aka "User Script Sandboxing") option set to YES.
• Make sure that all project developers use the same SwiftFormat version and config file.

[baphony]

Hello,

No rush, I am just wondering if there is something that I missed for this PR to be reviewed, or if I just need to wait for someone to have the time to look at it?

@calda @Blackjacx @mannylopez

Best regards,
Baptiste

[nicklockwood]

@baphony apologies for the delay, I will try to get to this soon. I have no objection to this in principle, but I don't use compiler plugins myself so I will need to familiarize myself with them in order to properly review the PR.

[baphony]

@baphony apologies for the delay, I will try to get to this soon. I have no objection to this in principle, but I don't use compiler plugins myself so I will need to familiarize myself with them in order to properly review the PR.

@nicklockwood No worries, I have added some details in the REAME file, but please let me know if you have any question, I will try to help