Bug#683908: gpsprune: doesn't properly use $http_proxy

[debian at activityworkshop.net]

I think there are two possibilities here - either the starter script 
gpsprune doesn't parse the proxy information properly and passes the 
wrong information to GpsPrune, or the networking stuff used by GpsPrune 
doesn't take any notice of what's passed in.  It would be very useful to 
know whether starting GpsPrune from the command line with
  java -Dhttp.proxyHost=10.0.0.1 -Dhttp.proxyPort=3128 -jar 
/usr/share/gpsprune/gpsprune.jar
makes things behave as you want.

Looking at Debian's gpsprune script (in 10.1), I can't see any reason 
why it wouldn't pass the port properly through - if I give it 
http://10.0.0.1:3128 then it appears to correctly split up the host and 
port, and pass both successfully onto GpsPrune.  So knowing whether the 
direct specification works or not would help rule out the gpsprune 
script as the problem.

Another problem I see in this script (although I'm not too familiar 
with bash), is what happens when you give a host but no port?  In the 
case of "http://10.0.0.1", it correctly identifies the host as 
"10.0.0.1", but the second sed command fails to find a match, and 
returns the whole $http_proxy variable.  So I end up with host=10.0.0.1 
and port=http://10.0.0.1 - surely that can't be right.  Perhaps it is 
rejected later and reset to 80 by the networking classes?  But I assume 
that rather than checking [ -z $proxyport ], it should be running a grep 
and looking at the return code to see whether a match was found or not.

Any Debian bash experts feel like commenting on this one?