Update to 1.2.3

2012-10-19 Keith Winstein <mosh-devel@mit.edu>

        * Version 1.2.3 released.

        * Security improvements:
                * Use OpenSSL AES implementation
                * Update AES-OCB implementation (Keegan McAllister)
                * Don't let bad server dictate IP (Felix Groebert)

        * New features:
                * Client hops ports to survive challenging client-side firewall
                * Server stops sending to save client power (Daniel Drown)
                * Set DiffServ code point and ECN-capable (Dave T\xc3\xa4ht)
                * Slow down if explicit congestion notification received
                * Warn about unattached Mosh sessions on login
                * Compatible with KDE konsole (uses BEL to terminate OSC)
                * Improved heuristic about color of predicted characters

        * Bug fixes:
                * Improved performance on systems with expensive time
                * No longer choke on "ffff::" address for hosts with IPv6
                * More conservative MTU and datagram sizing

        * Platform support:
                * Build on Solaris and IllumOS (Timo Sirainen, Ira Cooper)
                * Build on ARM with gcc 4.7 (Alexander Chernyakhovsky)

        * Licensing changes:
                * Allow distribution on Apple App Stores
                * Allow linking with OpenSSL

(wen)