refactor: use constants instead magic values

src/datasource-zabbix/constants.js

@@ -0,0 +1,16 @@
+// Editor modes
+export const MODE_METRICS = 0;
+export const MODE_TEXT = 2;
+export const MODE_ITSERVICE = 1;
+
+// Triggers severity
+export const SEV_NOT_CLASSIFIED = 0;
+export const SEV_INFORMATION = 1;
+export const SEV_WARNING = 2;
+export const SEV_AVERAGE = 3;
+export const SEV_HIGH = 4;
+export const SEV_DISASTER = 5;
+
+export const SHOW_ALL_TRIGGERS = [0, 1];
+export const SHOW_ALL_EVENTS = [0, 1];
+export const SHOW_OK_EVENTS = 1;