Changes to MirrorGET between r2 and r3

'''BitTorrent For Your HTTP Mirrors'''

Fetch segments of large files from different remote mirrors to increase download speed.

Implementations:
   * C implementation -->    * [C] implementation
   ** [Protothreads] based [http://www.rkeene.org/projects/info/resources/projects/mirrorget/mirrorget.c]
   ** [Pthreads] based version (not yet available)
   * Bash implementation (not yet available)

Legend

     Only in r2
     Only in r3
     -->      Modified slightly between r2 and r3