0.30.11 Support SRS signing mode.
0.30.10	Support SES
0.30.9	Support sendmail socket map.
0.30.8	Use HMAC instead of straight SHA to match reference implementation.
0.30.7	Pass SRS_DOMAIN to envfrom2srs.py
	Put SRS rewriting rule at end of EnvFromSMTP in pysrs.m4.
	Fix regex for is_srs macro in pysrs.m4.
0.30.6	set alwaysrewrite=True in envfrom2srs.py since pysrs.m4 skips local
	domains.
	Incorporate m4 macro from Alain Knaff for cleaner sendmail support.
0.30.5	Make sendmail maps use config file in /etc/mail/pysrs.cfg,
	so there is only only source to modify to change options.
	Add missing import for SRS.new()
0.30.4	Move global options to package module.  Rename Base.SRS to Base.Base.
