pyflakes cleanups
Enable vendordata for CloudSigma (LP: #1303986)
Add timeouts for reading/writing from/to to the serial console
Use dmidecode to detect if cloud-init runs in CloudSigma's infrastructure
open 0.7.6
add vendordata support to cloudsigma datasource
minor cleanups.

 * do not run dmidecode on arm.
 * line length
 * comment that 60 second time out is expected
CloudSigma: only poll on serial device after dmidecode check.

On systems with a ttyS1 and nothing attached, the read attempts
that the cloud sigma datasource would do would block.

Also, Add timeouts for reading/writting from/to the serial console
SmartOS test: do not require existance of /dev/ttyS1.