Add a take_every function.
Merge pull request #1635 from Raynes/takenth

Add a take_every function
Adjust code to style used in the codebase
Provide better error message for mix -e, closes #1639
Update CHANGELOG
Move to capture syntax
Minor style fix in Enum.take_every/2
Record docs adjustments
Improve invalid match and guard errors, closes #1673
Improve doctest stripping, closes #1678
Provide better exceptions for invalid unquote args, closes #1680
Correction of small typos in Regex docs.
Merge pull request #1711 from osaut/docs_regex

An example for Regex.compile and correction of small typos in Regex docs.
Fix handling of nested do expressions in EEx, closes #1710
Slightly tidy up IEx.Server
IEx now respects signals sent from user_drv, closes #1566
Document the dot as a special form

We include common examples, quoted expressions, and more.
Deprecate previous partial application syntax
Add Stream.unfold

This generates a possibly finite stream of values.
Make --sup the default for mix

Closes #1706