New: adding flags -help, -fail, and -quiet

I refactored everything to get the arguments from flag.
Changing time format of track to a more appealing one

Before it was something like

    2006-01-02 15:04:05.999999999 -0700 MST

and now it is formatted simpler, namely:

    2006-01-02 15:04:05 MST.

It also easier to change manually this way.
Bugfix and feature completion: total

The bugs fixed are that the path argument was not read correctly, and there
was a case when the usage message wasn't shown when it should have been.