Add support for multiple output files in different formats (#732)

internal/config/application.go

@@ -30,7 +30,7 @@ type parser interface {
 // Application is the main syft application configuration.
 type Application struct {
 	ConfigPath         string             `yaml:",omitempty" json:"configPath"`                                                         // the location where the application config was read from (either from -c or discovered while loading)
-	Output             string             `yaml:"output" json:"output" mapstructure:"output"`                                           // -o, the Presenter hint string to use for report formatting
+	Output             []string           `yaml:"output" json:"output" mapstructure:"output"`                                           // -o, the format to use for output
 	File               string             `yaml:"file" json:"file" mapstructure:"file"`                                                 // --file, the file to write report output to
 	Quiet              bool               `yaml:"quiet" json:"quiet" mapstructure:"quiet"`                                              // -q, indicates to not show any status output to stderr (ETUI or logging UI)
 	CheckForAppUpdate  bool               `yaml:"check-for-app-update" json:"check-for-app-update" mapstructure:"check-for-app-update"` // whether to check for an application update on start up or not

internal/config/registry_test.go

@@ -2,9 +2,10 @@ package config
 
 import (
 	"fmt"
-	"github.com/anchore/stereoscope/pkg/image"
 	"testing"
 
+	"github.com/anchore/stereoscope/pkg/image"
+
 	"github.com/stretchr/testify/assert"
 )