Add --copy to install command (fixes #962)
Update CHANGELOG
Don't update the progressbar if the value is invalid

Should fix conda/conda-build#224.
allow progressbar to handle too-small maxval

can come up for servers reporting incorrect
Content-Length, or requests decompressing content.

progress bar will sit at 100% while value >= maxval
use actual bytes read for download progress

instead of len(chunk), which may be decompressed and thus a different size
Merge pull request #1041 from minrk/raw-chunksize

use actual bytes read for download progress
Merge pull request #1040 from minrk/maxval

allow progressbar to handle too-small maxval
Update CHANGELOG
Merge remote-tracking branch 'conda/master' into feature/instructions