New verboseDebugging flag to pass --verbose to sc
Perform a download of sc during install

This allows someone to sudo npm install sauce-connect-launcher and not get
into a bad state where they are unable to permissions issues (subsequent
runs not as sudo will be unable to write sc to the module's dir).
Perform a download of sc during install. Closes #36
Merge branch 'sc-verbose-flag' of github.com:guardian/sauce-connect-launcher into guardian-sc-verbose-flag
New verboseDebugging flag to pass --verbose to sc. Closes #33
Adding release notes
Release v0.7.0.