Added link ends to role documentation.
Sorted the language options list alphabetically, and added missing options.
Prevent line wrapping after the dash of an option.
Added more option implication documentation.
Merge branch 'master' of git://git.haskell.org/ghc

Conflicts:
	docs/users_guide/flags.xml
Make DeriveTraversable imply DeriveFunctor/Foldable

Implements #9069
Added testcase for #9069
Update mod73 test output

to what I observe on travis and on my validate machine, even though my
local tree produces the previous output.
Use UnicodeSyntax when printing

When printing Haskell source, and UnicodeSyntax is enabled, use the
unicode sytax characters (#8959).
Only use UnicodeSytanx pretty printing if the locale supports it

using the same check as for unicode quotes.
Test case: GHCi uses UnicodeSyntax if the loaded file uses it.

Its marked as broken, as this does not work yet, but we are calling it a
day here soon, so I want this to be recorded (#8959).
Fix discarding of unreachable code in the register allocator (#9155)

A previous fix to this was wrong: f5879acd018494b84233f26fba828ce376d0f81d
and left some unreachable code behind.  So rather than try to be clever and
do this at the same time as the strongly-connected-component analysis, I'm
doing a separate reachability pass first.
supress warning of bang wildcard pattern-binding (i.e. let !_ = rhs). This fixes #9127
s/-hi-diffs/-ddump-hi-diffs/ in docs (#9179)
Test case for #9181 (:browse GHC.TypeLits panic)