Restore the dependencies installation parameter with new, SSM param-based format.

[jdrodjpl]

Marketplace application dependencies will now be defined as a set of SSM Parameters that are required to be in place before an application can be installed.

The following schema will be used in the metadata.json file for each Marketplace item:

	"Dependencies": # These are all the SSM Parameters whose existence will be checked before installation.
		# ${PROJ} and ${VENUE} will be substituted with the relevant values.
		{ "key_name": "/${PROJ}/${VENUE}/key_SSM_path" },
	"Apps": # If the above dependency SSM params are not all present, this list will be used to suggest to the user
			# additional applications they can install to fulfill the SSM param requirement.
		{ "app_name": { "MinimumVersion": "version" } },
	"OutputSsmParameters": # These are SSM parameters that the install process of this application is expected to make.
		# If they are not present once the application is installed, it will be considered a failed install
		# and the installing user will be alerted.
		["ssm_param_path"]
}