Merge pull request #77 from aplanas/master

Optimize a bit the image matching.
readd the typing sleep for now
make mouse_hide more reliable

by retrying till we have an absolute mouse pointer. I had to reverse
engineer qemu's vnc implementation to figure where the problem is. But
qemu has no mouse registered at the moment we connect to VNC and so
mouse moves are ignored - but they trigger a check if there is a mouse.
So we need to try one more time, till we know qemu has a mouse - fortunately
it tells us
Merge pull request #78 from os-autoinst/coolo_fix_mouse

make mouse_hide more reliable
Merge pull request #79 from os-autoinst/coolo_sleep_again

readd the typing sleep for now
Increase the margin from 50px to 150px.