adding setting to allow users to customize between binary vs SI/Metric units in UI.

fixes #330

webapp/backend/pkg/models/setting_entry.go

@@ -15,6 +15,7 @@ type SettingEntry struct {
 
 	SettingValueNumeric int    `json:"setting_value_numeric"`
 	SettingValueString  string `json:"setting_value_string"`
+	SettingValueBool    bool   `json:"setting_value_bool"`
 }
 
 func (s SettingEntry) TableName() string {

webapp/backend/pkg/models/settings.go

@@ -13,6 +13,7 @@ type Settings struct {
 	DashboardDisplay string `json:"dashboard_display" mapstructure:"dashboard_display"`
 	DashboardSort    string `json:"dashboard_sort" mapstructure:"dashboard_sort"`
 	TemperatureUnit  string `json:"temperature_unit" mapstructure:"temperature_unit"`
+	FileSizeSIUnits  bool   `json:"file_size_si_units" mapstructure:"file_size_si_units"`
 
 	Metrics struct {
 		NotifyLevel            int `json:"notify_level" mapstructure:"notify_level"`