Adding Recipients
Recipients can be added in three ways:
addTo(): Adds a recipient to the mail with a "To" header
addCc(): Adds a recipient to the mail with a "Cc" header
addBcc(): Adds a recipient to the mail not visible in the
header
getRecipients() serves list of the recipients.
clearRecipients() clears the list.
Additional parameter
addTo() and addCc() accept a second
optional parameter that is used as a human-readable name of the recipient for the
header. Double quotation is changed to single quotation and angle brackets to square
brackets in the parameter.