v0.8.0 (aws#443)

* Update CHANGELOG
* Bump 0.8.0 (without "beta")

v0.7.4-beta (aws#415)

* Bump to v0.7.4-beta
* Update CHANGELOG

v0.7.3-beta (aws#260)

* Bump to v0.7.3-beta
* Update CHANGELOG

v0.7.2 (aws#143)

v0.7.1

v0.7.0 (aws#97)

* Bring in historical changelog and add a section for 0.7.0
* Update README instructions
* Fix typescript templates