Auto merge of #3371 - trafficland:master, r=alexcrichton

Add -vv to the list of options printed by cargo --help.

diff --cc src/bin/bench.rs
Simple merge

diff --cc src/bin/build.rs
Simple merge

diff --cc src/bin/doc.rs
Simple merge

diff --cc src/bin/install.rs
Simple merge

diff --cc src/bin/run.rs
Simple merge

diff --cc src/bin/rustc.rs
Simple merge

diff --cc src/bin/rustdoc.rs
Simple merge

diff --cc src/bin/test.rs
Simple merge