Improve log output of PipHelper & LocalPipHelper
Improve log output of PipHelper & LocalPipHelper

Should make it easier to detect the reason for a broken pip install in
the future (e.g. non writable install directories).

foosel/OctoPrint,Jaesin/OctoPrint,Jaesin/OctoPrint,Jaesin/OctoPrint,foosel/OctoPrint,foosel/OctoPrint,foosel/OctoPrint,Jaesin/OctoPrint