Improve IDE code completion for Swift_SmtpTransport
merged branch Haprog/improve-code-completion (PR #325)

This PR was squashed before being merged into the master branch (closes #325).

Discussion
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Improve IDE code completion for Swift_SmtpTransport

Add @method doc blocks to Swift_SmtpTransport for setUsername(), getUsername(), setPassword(), getPassword(), setAuthMode() and getAuthMode() to improve IDE code completion for Swift_SmtpTransport.

Commits
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a4c597d Improve IDE code completion for Swift_SmtpTransport