refactor: expose generated code and client business logic to share with Kapacitor (#103)

* refactor: take clients out of internal

* refactor: move stdio to pkg

* Move internal/api to api

* refactor: final changes for Kapacitor to access shared functionality

* chore: regenerate mocks

* fix: bad automated refactor

* chore: extra formatting not caught by make fmt

pkg/stdio/stdio.go

@@ -0,0 +1,13 @@
+package stdio
+
+import "io"
+
+type StdIO interface {
+	io.Writer
+	WriteErr(p []byte) (n int, err error)
+	Banner(message string) error
+	Error(message string) error
+	GetStringInput(prompt, defaultValue string) (string, error)
+	GetPassword(prompt string, minLen int) (string, error)
+	GetConfirm(prompt string) bool
+}