[seph@directionless.org, andersk@mit.edu: add in even more places]

Add mach_absolute_time and gettimeofday timestamp implementations, and
fix clock_gettime check so that it can actually succeed

On most systems, even if __STDC_ISO_10646__ is not declared, wchar_t
will be correct in a UTF-8 locale. The client and server both enforce
a locale check on startup.

[andersk@mit.edu: Add byteorder.h to libmoshcrypto_a_SOURCES]

With automake 1.11, this gives us Linux kernel–style silent output
that makes warnings more obvious:

  GEN    userinput.pb.cc
  CXX    userinput.pb.o
  AR     libmoshprotos.a
  CXXLD  mosh-client

(Use ‘make V=1’ for the traditional verbose output.)

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

This turns off -Werror by default except in the Debian package.
-Werror is inherently unportable and breaks things on OS X.  While it
can cause problems in Debian too, this is at least a little better.

It also turns off -pedantic in src/protobufs, because apparently
protoc output doesn’t compile with -pedantic on all platforms.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

[andersk@mit.edu: No changes, but I note for the record that dh
 overrides require a debhelper (>= 7.0.50) dependency that should have
 been listed in the control file, and there was nothing to clean up
 README after it was copied.]

For better support of non-threaded Perl installations.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

Fixes #30 github issue.

This avoids duplicating a long expression in a future commit.

This allows min() to work properly on timeouts.

Even with future support for detaching and reattaching, this variable will keep
its original meaning.

This prevents errors about the missing README.  It also suppresses creation of
the standard INSTALL document, which is long and fairly useless.

This will cause GitHub to render the Markdown syntax.