REL v0.19.0

Initial commit for cucim

Authors:
- Gregory Lee (https://github.com/grlee77)
- Benjamin Zaitlin (https://github.com/quasiben)
- Gigon Bae (https://github.com/gigony)
- jakirkham (https://github.com/jakirkham)
- Ray Douglass (https://github.com/raydouglass)