Support port range as -p/--port PORT[:HIGHPORT].

Extend mosh and mosh-server to support parsing a high port from
the desired_port argument.  The first (low) port must not be
greater than the second (high) port.
If only one value is provided, behaviour is as before; bind
to one port.  Also tweak the formatting in mosh-server(1) synopsis
to be consistent.

This resolves mosh issue # 296.

Signed-off-by: Luke Mewburn <luke@mewburn.net>
Display results at end of configure.

Display configuration results at end of configure run,
including the version, c++ compiler, and various
compiler flag variables.

Signed-off-by: Luke Mewburn <luke@mewburn.net>
macosx: builds a universal package for i386, x86_64.
Friendlier error message when server does not support UDP port range.
Allow stopping (via kill -STOP) and "fg" to resume session
Make the 'lost contact' string more human-readable

Teach the 'lost contact' warning string about time units larger than
seconds. After 60 esconds it will switch over to using a time display
that looks like 1:23, or 1:02:34.

Fixes #321.

Signed-off-by: Kevin Ballard <kevin@sb.org>
Simplify implementation of human_readable_duration()
Make "elapsed time" human readable even when other error is displayed
Merge branch 'humane-times'

Closes #333
Verify $port_request defined before scanning it for error purposes
Use dup() instead of move semantics for Network::Socket
mosh-server: Fix bug where spins forever if process dies while disconnected
Adjust timeouts so server dies quicker, updates utmp slower
mosh-server warning on unattached servers checks that device exists
Allow suspend by keystroke (Ctrl-^ Ctrl-Z)

(based on patch by Nickolai Zeldovich)
Show infobar when Ctrl-^ is typed.
Document new Ctrl-^ Ctrl-Z sequence
Don't immediately clear network exceptions, even when problem solved
Update watchfile to fix Github breakage
We can't iterate over the object we are modifying

If subtract is called on itself, prefix and this is the same and the
iterator is invalid after modifying the underlaying object.

Instead just clear everyting.

Closes #354. Closes #355.