Update Ubuntu 12.04 boost from 1.46 to 1.48
Update Ubuntu 12.04 boost from 1.46 to 1.48

1.48 is required by python-sopnet, so this keeps the default
dependencies of both compatible in downstream CATSOP for Ubuntu 12.04.

fzadow/CATMAID,fzadow/CATMAID,fzadow/CATMAID,fzadow/CATMAID