Avoid building as root with `sudo make install`

When running `sudo make install`, we only want to run the actual install
as root, the building of the documentation and the distribution folder
should happen as the non-root user.

Related to #13728.
update vim indent file
Add help diagnostic messages

This adds ‘help’ diagnostic messages to rustc. This is used for anything that
provides help to the user, particularly the `--explain` messages that were
previously integrated into the relevant error message.
doc: Cleanup.

Remove ~~~ for code block specification. Use /// Over /** */ for doc
blocks.
doc: Methods for result::Result.
doc: Methods for option::Option
doc: Backticks and spelling mistakes.
doc: Remove "see above".
from_str has an impl for uint, not Option<uint>
fix for vim < 7.4.355
Refactor `Vec::map_in_place` to move code out of `PartialVec`

Additionally, support zero-sized types.
Ignore two gdb tests on windows that are failing on the bots
std: Don't require bitflags! be u32

If you didn't have a trailing comma at the end of the variants, you could use
any type you wanted, but if you used a trailing comma the macro would
erroneously require the bits be a u32.
Do not attempt to autoderef `!`

This prevents error spam when attempting to look up overload traits.
Disallow dereference of `!`

Later compiler passes are not prepared to deal with deref of
`ty_bot` and will generate various ICEs, so disallow it outright for now.

Closes issue #17373
Disallow index of `!`

This avoids ICEs in later passes that cannot cope with this construct
Add regression test for issue #17373
Add test that `!` cannot be indexed
auto merge of #17404 : alexcrichton/rust/bitflags-u32, r=sfackler

If you didn't have a trailing comma at the end of the variants, you could use
any type you wanted, but if you used a trailing comma the macro would
erroneously require the bits be a u32.
libsyntax: Explicit error message for sugared doc comments.

Display an explicit message about items missing after sugared doc
comment attributes. References #2789.