misc: added changealt command
mavflightview: support more msg types
console: Show percentage of packets received.
options: Allow multiple --cmd arguments to be specified as arguments

Although the existing code properly splits cmds based on a ; separator
I've had a couple DroneAPI users get bitten when they tried to specify
multiple --cmd args (which would be natural to try).  Mavproxy was
implicitly ignoring all but the the last --cmd.
mavproxy_misc: Added "land" and "land abort" commands.
removed old land command
Add *.egg-info to .gitignore
Retire Yahoo map services and default to OviHybrid

Yahoo! seems to have decommissioned their map tile servers;
as of 10/31/2014 they're returning HTTP 503/504 errors.
fix GPS fix tracking
Add --daemon option to let mavproxy not read from stdin
Add a signal handler so we can nicely run module unload code on shutdown

I go ahead and run the main_loop always in a child thread, because it
makes it more like the old mavproxy behavior.  If a daemon I check every
100ms if we have been asked to quit.
name threads for easier profiling/debugging
Add a compdebug bitmask setting which can be used to turn off code

for profiling purposes
Add --profile option to allow running mavproxy under the yappi profiler.

Note: I used yappi because the cprofiler doesn't automatically handling
profiling child threads.  Yappi does.

I'm careful to only do the import if the --profile is passed in, so that
mavproxy won't break on platforms where that lib is not installed.
Make packet inspection use sets, for slight speed improvement

About 1% on an Edison.