Merging originchecks branch, squashing commit of the following:

commit 99c1bba3f743b8424f80da2316bd5819c1d62d87
Author: Alex Sergeyev <asergeyev@dyn.com>
Date:   Mon Apr 7 22:33:59 2014 -0400

    Adding support for --origin list of allowed origin names.

commit 83ca93ba62d31f0eea532abcf1e2d599379479f5
Author: Alex Sergeyev <asergeyev@dyn.com>
Date:   Mon Apr 7 10:08:14 2014 -0400

    This is rather big refactoring...

    * changed how origin check is integrated
    * added RemoteInfo struct to not duplicate dns lookup in two places
    * added requestInfo struct to not create functions with 5+ arguments
    * fixed how origin and host headers are compared (using SplitHostPort)

commit 40c6e2a5a3fee39e678a5524d3f8088b936d95d2
Author: Alex Sergeyev <asergeyev@dyn.com>
Date:   Sun Apr 6 22:57:04 2014 -0400

    Added support for same origin policy via --sameorigin flag

commit e7e8331e7b8df02af974872f8088034bf8ffc99a
Author: Alex Sergeyev <asergeyev@dyn.com>
Date:   Sun Apr 6 21:42:40 2014 -0400

    Added config structure fields to keep origin restrictions info.

commit dd6644f272ade9c57ce027880b602002aac28a38
Author: Alex Sergeyev <asergeyev@dyn.com>
Date:   Sun Apr 6 21:41:44 2014 -0400

    Added help for origin restricting flags to be implemented.