Transfer ownership of ember-cli-materialize

[leonidez]

Hello @sgasser, my name is Leonidez. I work at Poetic Systems in Houston, Texas and we're interested in becoming the maintainers of ember-cli-materialize. We've made a big investment in ember over the last year and we'd like to incorporate the work you've done into a fully developed package. For reference to our related work please refer to our github: https://github.com/poetic/. Thank you.

[sgasser]

Hi @leonidez, at the moment I'm not interested to give up maintainer-ship.
Pull requests are always welcome. 😄
After some pull requests by Poetic Systems we can talk about it again.