Clean up output

Currently the output looks like this:

info: syncing channel updates for 'stable'
info: downloading component 'rust'
info: syncing channel updates for 'nightly'
info: downloading component 'rustc'
46.40 MiB / 46.40 MiB (100.00%) 4.57 MiB/s ETA: 0s                
info: downloading component 'rust-std'
58.85 MiB / 58.85 MiB (100.00%) 3.57 MiB/s ETA: 0s                
info: downloading component 'rust-docs'
6.25 MiB / 6.25 MiB (100.00%) 3.00 MiB/s ETA: 0s                
info: downloading component 'cargo'
4.06 MiB / 4.06 MiB (100.00%) 2.37 MiB/s ETA: 0s                
info: installing component 'rustc'
info: installing component 'rust-std'
info: installing component 'rust-docs'

The "info" is bold and quite redundant. It actually carries the least information, why is it highlighted?
It would be much nicer to have something like cargo's output, i.e.:

    Updating registry `https://github.com/rust-lang/crates.io-index`
 Downloading rust-gmp v0.2.10
 Downloading rustc-serialize v0.3.19
   Compiling rustc-serialize v0.3.19
   Compiling libc v0.2.9

Here the verbs are bold and carry the most important information.

The issue names no files, tests, or entry points. Start by tracing where rustup emits the shown status and progress lines, then compare the formatting with the cargo examples; it is done when the redundant info labels are no longer emphasized and the important verbs receive the emphasis described in the issue.