tests: add missing files to Makefile.am
fixed 204 response handling, added new Test-204.px
progress: Split update into update and draw
Add --show-progress to force  display progress bar

This is a relatively large commit that implements two major features:

1. Implement --show-progress switch to force the display of the progress bar in
   any verbosity level
2. Edit the implementation of the progress bar so that the filename is displayed
   in the same line.
Aesthetic changes and bug fixes for progress bar
Merge branch 'master' into spring_cleaning