Fix up a bunch of things indicated by clippy#1012

Merged

bors merged 10 commits intorust-lang:masterfrom daniellockyer:clippy-fixes

Mar 27, 2017

+40-40

Commits on Mar 26, 2017

Switch to more specific assert macros
Daniel Lockyer
committed
Remove unnecessary reference
Daniel Lockyer
committed
Switch to more suitable functions/simplify closures
Daniel Lockyer
committed
Remove explicit return
Daniel Lockyer
committed
Fix documentation
Daniel Lockyer
committed
Remove unnecessary use of format!()
Daniel Lockyer
committed
Switch String to str
Daniel Lockyer
committed
Switch single character double-quote usage to single-quote
Daniel Lockyer
committed
Use reference instead of .iter()
Daniel Lockyer
committed
Remove explicit use of &mut
Daniel Lockyer
committed