Fix code example for Message#resent_sender=

The code example for Message#resent_sender= contains the wrong method name
Merge pull request #520 from RKushnir/patch-1

Fix code example for Message#resent_sender=
Docs: mail.from/to/bcc/etc return emails only. Closes #529.
Correct example calls to preamble and epilogue in README
Merge pull request #537 from jpmckinney/master

preamble and epilogue correction in README
Replace Treetop parser with a Ragel based parser
AddressListsParser: Don't add an extra address to the address list when it ends with a space.
ReceivedParser: don't error out on quoted strings in a received header
common.rl: use clearer .* in dot_atom_text, instead of (.+)?
Correctly parse addresses that begin with a comment.