# Functions
FoldValue will take an unfolded or perhaps partially folded value from an email and fold it.
MakeHeaderFieldMatch trims space and lowers the case of a header name for comparison purposes.
NewBody builds a new body with the given content bytes.
NewHeader creates a new header.
NewHeaderField constructs a new header field using the given name, body, and line break string.
NewHeaderFieldParsed constructs a new header field using the given name, body, line break, and original.
NewMessage builds a new basic email message from the given header and body.
UnfoldValue will take a folded header line from an email and unfold it for reading.
# Constants
"\r" - Commodores and old Macs.
"\r\n" - Network linebreak.
indent placed before folded lines.
we forceably break headers and 7bit/8bit bodies lines longer than this.
"\n" - Unix and Linux.
"\n\r" - weirdos.
we prefer headers and 7bit/8bit bodies lines shorter than this.
# Structs
Body is a basic wrapper around a slice of bytes of data.
Header represents an email message header.
HeaderField represents an individual field in the message header.
Message represents an email message and body.