* Initial dynamic shapes doc

* Basics on dynamic shapes, with example code

* Add glossary defs and dynamic shapes example

* Slightly better organization

* Address make style check failure, maybe

* Test dynamic shapes doc w 0.27.0-rc.0+9aa81d9

* Resolve doc build error w new opset versioning

* Review comments addressed

* Add theme-relevant revised illustrations from collab_ngai

* style

* Style fixes

* Run make style-apply with clang-format-3.9