ubuntu-bug should check for internet connection before it starts doing anything

[Teo]

Steps to reproduce:

1. Disconnect from the internet
2. from a terminal, run "ubuntu-bug some-package"

Expected result: should immediately warn me that I am not connected to the internet.

Observed result: wastes my time collecting bug data and, in some cases depending on the package, prompting for the sudo password. Only after that, when it tries to connect to send the bug report, does it realize there's no internet connection and it issues an error saying so.

Also note that there's no "Retry" button, which makes the issue worse.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: apport 2.19.1-0ubuntu5
ProcVersionSignature: Ubuntu 4.2.0-23.28-generic 4.2.6
Uname: Linux 4.2.0-23-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Jan 18 21:33:57 2016
InstallationDate: Installed on 2013-10-11 (829 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
PackageArchitecture: all
SourcePackage: apport
UpgradeStatus: Upgraded to wily on 2016-01-18 (0 days ago)

[Brian Murray (brian-murray)]

It should not check if --save is used though.