Pushing changes for testing harness before my next meeting. Adding working exec library and sample code

Signed-off-by: Kris Nóva <kris@nivenly.com>

sample-app/app.go

@@ -0,0 +1,41 @@
+package sampleapp
+
+import (
+	"github.com/kris-nova/logger"
+
+	photoprism "github.com/kris-nova/client-go"
+)
+
+type SampleApplication struct {
+}
+
+func New() *SampleApplication {
+	app := &SampleApplication{}
+	return app
+}
+
+// These are the bash scripts that can be used
+// to start/stop the Photoprism test application
+var (
+	CreateCommand  = `./pcreate`
+	DestroyCommand = `./pdestroy`
+	LogsCommand    = `./plogs`
+	StartCommand   = `./pstart`
+	StopCommand    = `./pstop`
+)
+
+func (a *SampleApplication) Start() error {
+	logger.Info("Starting Application...")
+	script := NewScript(StartCommand)
+	return script.Interpret()
+}
+
+func (a *SampleApplication) Stop() error {
+	logger.Info("Stopping Application...")
+	script := NewScript(StopCommand)
+	return script.Interpret()
+}
+
+func (a *SampleApplication) GetAuth() photoprism.ClientAuthenticator {
+	return nil
+}