Golang implementation of /api/1.1/parameters POST can't handle arrays

[ocket8888]

The route at /api/1.1/parameters in Perl used to accept either a single parameter e.g.

{
	"name": "test",
	"value": "quest",
	"configFile": "records.config",
	"secure": false
}

or an array of such objects e.g.

[
	{
		"name": "test",
		"value": "quest",
		"configFile": "records.config",
		"secure": false
	},
	{
		"name": "foo",
		"value": "bar",
		"configFile": "records.config",
		"secure": false
	}
]

but the ability to handle the second case was lost in the translation to Go.

[ocket8888]

This was closed by #4356