auto merge of #12940 : cadencemarseille/rust/time-doc, r=alexcrichton
auto merge of #12942 : alan-andrade/rust/docathon-getopts, r=alexcrichton

https://docs.google.com/spreadsheet/ccc?key=0An9tLRVf1SSfdE9jX1Q2QkhiUGVwTnh5YTJnMHVUYXc&usp=sharing#gid=6
auto merge of #12944 : mcpherrinm/rust/master, r=alexcrichton
auto merge of #12945 : cadencemarseille/rust/vec_ng-as_mut_ptr, r=alexcrichton
De-@ Session usage.
De-@ ty::ctxt usage.
De-@ tyencode::ctxt and related parts of astencode.
De-@ liveness.
De-@ type checking contexts.
De-@ trans contexts.
De-@ reachable.
De-@ filesearch.
De-@ CStore uses.
De-@ ParseSess uses.
De-@ resolve_lifetime.
De-@ typeck::check::method.
De-@ gather_loans.
De-@ move maps and rework parts of trans.
De-@ codemap and diagnostic.
Refactor pprust a bit.