Fix progress bar calculation bug in download

Download progress bar was using the number of missing blocks as
its length.
It now uses the total number of blocks in the file, instead.
Unescape escaped names before printing to console
Revert "Escape control characters in HTTP body, when json"

This reverts commit 556d5f15885c1a04ca36120b820157d568ef348e.
For more information, please see the discussion on Issue #32.
Bump version to 0.13rc3
Merge branch 'release-0.13' into debian-release-0.13
Bump version to 0.13~rc3-1~wheezy

Signed-off-by: Ilias Tsitsimpis <iliastsi@grnet.gr>