minor #750 Add a return value description to Swift_Mailer::send method (vhraban)
minor #750 Add a return value description to Swift_Mailer::send method (vhraban)

This PR was merged into the 5.x branch.

Discussion
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Add a return value description to Swift_Mailer::send method

I was trying to figure out what are the possible return types for send method, and send method PHPDoc was not helpful at all. I had to go through documentation and look for that, but it would be so much easier if the comment was a little bit more descriptive.

**Feature**: Add a description for Swift_Mailer::send method return type.

I hope this PR will help people like me and will save someone those precious couple of minutes

Commits
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64b732f Add a return value description to Swift_Mailer::send method

jamesggordon/swiftmailer,denpamusic/swiftmailer,Rotzbua/swiftmailer,voku/swiftmailer,gencer/swiftmailer,c960657/swiftmailer,tweakers-dev/swiftmailer,c960657/swiftmailer,michabbb-backup/swiftmailer,tweakers-dev/swiftmailer,denpamusic/swiftmailer,swiftmailer/swiftmailer,jamesggordon/swiftmailer,Rotzbua/swiftmailer,voku/swiftmailer,gencer/swiftmailer,michabbb-backup/swiftmailer,swiftmailer/swiftmailer