Set default_flow_style for yaml jinja filter

[enykeev]

It is my impression that this filter is mainly used to produce readable representation of the object. Unless default_flow_style is strictly defined, yaml dumper would pick the one it seem appropriate producing quite different formatting for pretty similar kind of input.

Flow style

{author: st2-dev, description: StackStorm pack management, email: info@stackstorm.com,
name: st2, version: 0.1.2}

vs block style

author: st2-dev
description: st2 content pack containing github integrations
email: info@stackstorm.com
keywords:
- github
- git
- scm
name: github
version: 0.4.0

[emedvedev]

LGTM

[codecov-io]

Current coverage is 77.15% (diff: 100%)

Merging #3051 into master will increase coverage by 0.25%

@@ master #3051 diff @@
==========================================
Files 430 430 Lines 21997 21997 Methods 0 0 Messages 0 0 Branches 0 0 ==========================================
+ Hits 16914 16970 +56 + Misses 5083 5027 -56 
Partials 0 0 

Diff Coverage	File Path
•••••••••• 100%	st2common/st2common/jinja/filters/data.py

Powered by Codecov. Last update 02e3c95...cbd6097

[arm4b]

http://pyyaml.org/wiki/PyYAMLDocumentation#FrequentlyAskedQuestions
+1

[Kami]

Good catch - LGTM, 👍

(we already do this in some places, but yeah it's a good idea to do it everywhere and be consistent)