PuTTY 0.66 GSS-API keyex 1.0

Changes compared to upstream PuTTY 0.66:

• Support for GSS-API key exchange and gssapi-keyex authentication.
• Support for Heimdal GSS-API.
• 64-bit binaries and installer.
• Data Execution Prevention enabled for all binaries.
• Binaries and installer signed using Microsoft Authenticode.
• Source compiles with MinGW32/64.

Changes compared to PuTTY 0.64 GSS-API keyex 1.1:

• Switched certificate for Authenticode so that signatures no longer expire when the signing certificate does.
• Security fix: an escape sequence which used to make PuTTY's terminal code read and potentially write the wrong memory is fixed. See vuln-ech-overflow.
• Bug fix: better Unicode handling in Windows PuTTY keyboard messages, so it should now work better with WinCompose.
• Bug fix: jump lists on Windows 10 should now work.
• There's now a set of command-line options to enable session logging.
• &P in the log file name now substitutes in the port number from the configuration.
• Incoming connections to PuTTY tools (to forwarded ports and to the connection-sharing socket) now log their source address or pid, where facilities exist to do so.
• Cryptography speedup on 64-bit Unix platforms by using gcc and clang's __uint128_t built-in type.
• Bug fix: the configuration dialog is no longer accidentally invisible in some Windows Vista display themes.
• Bug fix: the Windows PuTTY GUI no longer becomes unresponsive if the server sends a continuous flood of data. (Sorry! We fixed that once before, but it came back in 0.64.)
• Bug fix: PSFTP now returns a failure exit status if a command fails in a batch-mode script.
• Bug fix: ESC [ 13 t can no longer elicit an invalid escape sequence as a response.