bootstrap: Earlier grabbing of edeploy-roles

As per issue #77, we can have issues at reporting which profile fails as
the information was arriving too late.

This patch aims at printing as soon a possible inside the configure
script the name of the profile that matched. Even if the configure is
totally broken, this information will be printed to the configure file.

This way, the edeploy client will be in position to reincrement the
role's counter even if the configure was totally broken.
init: Creating /dev/null as soon a possible

We had a message that /dev/null didn't exist while starting up the
bootstrap.

Let's avoid it by creating /dev/null as soon as possible.
init: Printing command line at boot time

It's pretty useful getting the command line that got used during
booting. This could help understanding why a server was behaving like
this way.
run_kvm: Checking curl in all cases

If curl isn't available, run_kvm will fail. So let's check it's present.