Change password generator
Change password generator

It adds lower and upper letters

JIRA: DOVETAIL-747

Change-Id: I4bdfcbf31a6dae4aa555fca3d42bbdec514a2b6b
Signed-off-by: Cédric Ollivier <d48310251a4a484d041bc5d09a9ac4d86d20f793@orange.com>

opnfv/functest,opnfv/functest