* Article "Architecture" is too small. It makes sense to add more
information. - Added some more information
* I think we need to change "How to write an Action Plugin" to just
"How to write a custom action". I think the word "plugin" here is
not important from user perspective - Done
* I think we need to change "How to extend YAQL with a new function"
to "How to write a custom YAQL function" and put it right next to
"How to write a custom action". That would be more consistent.
- Done
Change-Id: I9b43694072cb23271e33440741204da3e10b89ac
Partial-Implements: blueprint mistral-doc
d914e289dd