PLT-6471 Properly panic when translations can't be loaded (#6414)

* PLT-6471 Properly panic when translations can't be loaded

* Print usage messages when errors occur during CLI initialization

* Reverted behaviour of FindDir and added second return value to it

* Fixed merge conflict

app/auto_posts.go

@@ -41,7 +41,7 @@ func NewAutoPostCreator(client *model.Client, channelid string) *AutoPostCreator
 func (cfg *AutoPostCreator) UploadTestFile() ([]string, bool) {
 	filename := cfg.ImageFilenames[utils.RandIntFromRange(utils.Range{Begin: 0, End: len(cfg.ImageFilenames) - 1})]
 
-	path := utils.FindDir("web/static/images")
+	path, _ := utils.FindDir("web/static/images")
 	file, err := os.Open(path + "/" + filename)
 	defer file.Close()
 

app/saml.go

@@ -42,7 +42,8 @@ func WriteSamlFile(fileData *multipart.FileHeader) *model.AppError {
 		return model.NewLocAppError("AddSamlCertificate", "api.admin.add_certificate.open.app_error", nil, err.Error())
 	}
 
-	out, err := os.Create(utils.FindDir("config") + filename)
+	configDir, _ := utils.FindDir("config")
+	out, err := os.Create(configDir + filename)
 	if err != nil {
 		return model.NewLocAppError("AddSamlCertificate", "api.admin.add_certificate.saving.app_error", nil, err.Error())
 	}

app/user.go

@@ -709,7 +709,8 @@ func CreateProfileImage(username string, userId string) ([]byte, *model.AppError
 
 	initial := string(strings.ToUpper(username)[0])
 
-	fontBytes, err := ioutil.ReadFile(utils.FindDir("fonts") + utils.Cfg.FileSettings.InitialFont)
+	fontDir, _ := utils.FindDir("fonts")
+	fontBytes, err := ioutil.ReadFile(fontDir + utils.Cfg.FileSettings.InitialFont)
 	if err != nil {
 		return nil, model.NewLocAppError("CreateProfileImage", "api.user.create_profile_image.default_font.app_error", nil, err.Error())
 	}