Customize configuration secured properties

[smoneuse]

It would be nice to have a security syntax on seedstack configuration properties, to avoid their appearence in the outputs (logs, diagnostics , ... ).

By default, properties like "password" are already secured, the idea is to customize the properties withing the configuration that will be hidden.

As an example the syntax could be : <<...>> for properties to be secured.

sampleConfiguration:
	unSecuredValue: Safe value can be logged
	<<securedValue>>: sensible value is hidden
        fooBarProperty<sampleProfile>: unsecured in profile "sampleProfile"
       <<fooBarProperty>><secondProfile>: secured in profile "secondProfile"

It would also be nice to be able to secure an entire sub-tree :

anotherConfiguration:
	myProperty: Safe value won't be hidden
	<<subTree>>:
		value1: will be hidden
		value2: will be hidden too