Don't print `Running` for commands that aren't run

Also print the commands only right before they're actually run.

Closes #215
Always rebuild dist dir in "make dist" or install
auto merge of #559 : mbrubeck/cargo/make-install-fix, r=alexcrichton

This fixes an issue where `make dist` incorrectly does nothing after the source has changed and been rebuilt.  It also prevents `make install` from installing outdated files from the `dist` directory.
Allows bootstrapping win64 from win32 snapshot.
Remove triple = 'i686-pc-mingw32' once win64 snapshot is made.

Signed-off-by: Peter Atashian <retep998@gmail.com>
Merge commit '314d47749a79d0382eea1b710456b038a1ac84c0' into win64
Switch the URL from which nightlies are downloaded
auto merge of #562 : alexcrichton/cargo/win64, r=alexcrichton
Update "Contributing to the Docs"
auto merge of #555 : alexcrichton/cargo/issue-215, r=brson

Also print the commands only right before they're actually run.

Closes #215
Center main content in Safari
auto merge of #567 : EduardoBautista/cargo/fix-centering-on-safari, r=alexcrichton

The website is not centered in Safari.
Fix `make dist` and distcheck breakage

Fixes a regression from #559.
auto merge of #568 : mbrubeck/cargo/dist-fix, r=alexcrichton

Fixes a regression from #559.
Update all dependencies

This fixes some breaking changes with git2-rs, fixes a bug in tarball generation
from tar-rs, and fixes warnings with flate2-rs
auto merge of #564 : EduardoBautista/cargo/contributing-to-docs, r=alexcrichton

The docs are now in the main cargo repository.
Don't clone remote repos, use fetch instead

When cloning a remote repository, the default behavior of libgit2 is to only
update the local ref that's actually checked out, when we actually would prefer
to update all refs of the remote repo. This removes a call to clone() to a
init_bare() + fetch() which should update all refs accordingly

Closes #565
Fix bug in list_file_walk when cwd != path

Previously this was calling .is_file() on a relative path.  This would fail if
the path was not relative to the current working directory, for example when
fingerprinting a path dependency.
Test for build command fingerprints in path deps

This tests the fix for list_files_walk from #561.
Fix tests on Mac builders

Comparing URIs in /tmp was failing because of symlinks.
Fix list_files_git for paths in subdirs of a repo

list_files_git previously assumed that the package was always at the root of
the git repository.  This broke when trying to list files for a package in a
subdirectory of a repo, or in other cases, e.g. if the user's home directory
is a git repo.