The new password hash property is called secure_password in the config
file. `loolconfig` tool should be used to set the password hash in
appropriate format with desired salt length, password length, number of
iterations in PBKDF2.
To be backward compatible, plain-text password for admin-console in
config file is still accepted in case secure_password property is
missing from the config file.
Change-Id: If229999dac62856e368555c0242c4aa6f8061fba
A normal usage to set the admin password would be like :
loolconfig set-admin-password --config-file ./loolwsd.xml
Other command line options can also be given, like --pwd-salt-length,
--pwd-hash-length, --pwd-iterations.
Change-Id: I2a6f8d25e068b53a3f945426f0779c8410b2c8ba
