[Xastir] Volcano Symbol plus changing to igating

[Curt Mills]

Thanks go to Dale Huguley for the new volcano symbol, which replaces
the smokestack symbol we had before.  Dale is putting out packets
from the weather server for major volcanic ash & eruption events,
and a volcano seemed to make more sense for that application.  You
can see one down in South America right now if you're hooked to
firenet.

A few changes went in for igating.  We now refuse to gate under more
conditions.  Here's a summary of what sorts of things we'll drop on
the floor:


Gating to internet, drop packets that have/are:
-----------------------------------------------
    Empty info/path/callsign fields
!   Info field starting with '?' (General Queries)
    Packets from the igate callsign
    Third party
    "TCPIP"
    "TCPXX"
    "NOGATE"
    "RFONLY"


Gating to RF, drop packets that have/are:
-----------------------------------------
    Empty info/path/callsign fields
!   Info field starting with '?' (General Queries)
    Packets where both src and dest have been heard on local RF
    Heard over an interface within the last 29 seconds
    Sent over RF within the last 29 seconds
    "TCPXX"
!   "NOGATE"

* Destination callsign must have been heard on RF within the last
* hour.  We don't currently do a path-distance check, but probably
* should.


Gating to RF of NWS messages, drop packets that have/are:
---------------------------------------------------------
    Empty info/path/callsign fields
    NWS stations not listed in the nws-stations.txt file
    Heard over an interface within the last 29 seconds
    Sent over RF within the last 29 seconds
    "TCPXX"
!   "NOGATE"


All of these are implemented in CVS except for those marked with an
asterisk.  New features are marked with a '!'.

-- 
Curt Mills, WE7U                    hacker_NO_SPAM_ at tc.fluke.com
Senior Methods Engineer/SysAdmin
"Lotto:    A tax on people who are bad at math!"
"Windows:  Microsoft's tax on computer illiterates!" -- WE7U
"The world DOES revolve around me:  I picked the coordinate system!"