Add switch and switchback Cmd

Add switch and switchback Cmd

z/switchBackCmd.go

@@ -0,0 +1,26 @@
+package z
+
+import (
+  "github.com/spf13/cobra"
+)
+
+var switchBackCmd = &cobra.Command{
+  Use:   "switchback",
+  Short: "switchback to the task before the last one",
+  Long:  "End running activity and resume the task which was before, which can either be kept running until 'finish' is being called or parameterized to be a finished activity.",
+  Run: func(cmd *cobra.Command, args []string) {
+
+    finish = switchString
+    finishTask(FinishOnlyTime)
+
+    finish = ""
+    begin = switchString
+    resumeTask(2)
+  },
+}
+
+func init() {
+  rootCmd.AddCommand(switchBackCmd)
+
+  switchBackCmd.Flags().StringVarP(&switchString, "begin", "b", "", "Time the new activity should begin at and the old one ends\n\nEither in the formats 16:00 / 4:00PM \nor relative to the current time, \ne.g. -0:15 (now minus 15 minutes), +1.50 (now plus 1:30h).")
+}