Add HashiCorp Nomad provider (#483)

* provider: adding Nomad provider

* updating CONTRIBUTING.md with Nomad provider

* updated README.md by adding the Nomad provider

* fix typo

* adding nomad/api and nomad/testutil deps

* adding Nomad binary dependency for provider tests

* fixed the nomad binary download command step and added tolerations to the nomad provider.

* adding nomad provider demo gif

* adding my name to authors

* adding two missing go-rootcerts files after dep ensure

* delete pod comment

vendor/github.com/mitchellh/reflectwalk/location.go

@@ -0,0 +1,19 @@
+package reflectwalk
+
+//go:generate stringer -type=Location location.go
+
+type Location uint
+
+const (
+	None Location = iota
+	Map
+	MapKey
+	MapValue
+	Slice
+	SliceElem
+	Array
+	ArrayElem
+	Struct
+	StructField
+	WalkLoc
+)