Correct RFC reference in time::Tm::rfc3339 docs

Fixes #16158
Change strptime::match_strs to use borrowed rather than owned strings

Also modernise a few constructs in match_strs().
Fix API docs css reversing elements that it shouldn't

remove unneeded `pre.rust a' selector

move transform into `.test-arrow`

fixes #16138
Use hello_world instead of the guessing_game
Move caret under the 'x' variabe
collections: Implement Eq for DList, RingBuf, TreeMap, TreeSet
collections: Implement Ord for DList, RingBuf, TreeMap, TreeSet
collections: Implement FromIterator/Extendable for BitvSet
mk: Add missing colon
auto merge of #16163 : anguslees/rust/strptime-str, r=alexcrichton

Also modernise a few constructs in match_strs().
auto merge of #16164 : anguslees/rust/rfc3999, r=alexcrichton

Fixes #16158
auto merge of #16165 : tinaun/rust/newcss, r=alexcrichton

remove unneeded `pre.rust a' selector

move transform into `.test-arrow`

fixes #16138
auto merge of #16175 : EduardoBautista/rust/fix-guessing-game-appearing-early, r=steveklabnik

Solves: https://github.com/rust-lang/rust/issues/16162
auto merge of #16177 : nham/rust/collections_15294_eq_ord, r=alexcrichton

This implements:

 - Eq and Ord for DList, RingBuf, TreeMap and TreeSet
 - FromIterator and Extendable for BitvSet

cc #15294
auto merge of #16181 : brson/rust/colon, r=kballard