Explain the behavior of the policy attribute
Whitespace fixes
Updated DC documentation for 3.6.0

Mostly the `sketchify` documentation, but made some other changes too.
Change: Improve examples for listing and defining classes
Merge pull request #616 from nickanderson/classes

Change: Improve examples for listing and defining classes
Change: Whitespace and policy syntax cleanup
Merge pull request #623 from nickanderson/promise_types_formatting

Change: Whitespace and policy syntax cleanup
Added an example
Small fixes
Merge pull request #559 from lra/explain_policy

Explain the behavior of the policy attribute
Fixed typo.
Merge pull request #605 from zzamboni/update-dc-docs

Updated DC documentation for 3.6.0
Point out non-convergent behavior of preserve_all_lines.

Point to empty_file_before_editing attribute to ensure convergent
outcome.
added doc for sys.piddir and sys.logdir
Merge pull request #624 from basvandervlies/piddir_logdir_patch

added doc for sys.piddir and sys.logdir
Fixed general examples page
Merge pull request #150 from TekHus/cookbook-json

Fixed general examples page
Merge pull request #625 from KevWright/master

Fixed general examples page
Testing bullets
Merge pull request #151 from TekHus/cookbook-json

Testing bullets