docs: added missing libssh2_session_handshake.3 file
docs: fixed a bunch of typos
COPYING: bump the copyright year
Updated copyright year.
MinGW build: Fixed redefine warnings.
MinGW build: some GNUMakefile tweaks.

Added architecture autodetection; added switches to CFLAGS and
RCFLAGS to make sure that the right architecture is used.
Added support to build with WinCNG.
NMake build: added support for WinCNG build.
NMake build: fixed LIBS settings.
sftpdir.c: added authentication method detection.

Stuff copied over from ssh2.c to make testing a bit easier.
MinGW build: some more GNUMakefile tweaks.

test/GNUmakefile: added architecture autodetection; added switches to
CFLAGS and RCFLAGS to make sure that the right architecture is used.
Added support to build with WinCNG.
configure: change LIBS not LDFLAGS when checking for libs

Closes #289

Patch-by: maurerpe
build: updated dependencies in makefiles.