Update engine for refinerycms 3.0.0

[bricesanchez]

• Add new dependencies
• Use new way to precompile assets
• Use new icons set in admin
• Use new way to permit params

[unixcharles]

Hey Brice, thanks for your help.

LGTM but we're going to have investigate the test failure.

[unixcharles]

I added you to the collaborators, feel free to merge green PR that have a :+1: review

[bricesanchez]

Thanks @unixcharles :)

[bricesanchez]

Is it ok for you @unixcharles ? :)

[unixcharles]

:+1:

[bricesanchez]

Thank you !