Add option to display abook length

[aylen384]

Maybe cache the info within the abook folder?

Sample code for mp3:

#!/usr/bin/python                                                                                                                                              

import glob
from mutagen.mp3 import MP3 
files = glob.glob ('*.mp3')
myTotal = 0 
 
def fix_time( seconds ):
  hours = int(seconds) / 3600
  seconds = seconds % 3600
  minutes = int(seconds) / 60
  seconds = seconds % 60
  seconds = int(seconds)
  return "%d:%02d:%02d" % (hours, minutes, seconds)
 
for eachfile in files:
    audio = MP3(eachfile)
    eachTime = fix_time( audio.info.length )
    print("File: %s - Length: %s" % (eachfile, eachTime))
    myTotal = myTotal + audio.info.length
 
newTotal = fix_time( myTotal )   
print("Total time: %s" % (newTotal))