Support Rails 6

[shanecav84]

Wanted to test my own apps and needed to do this locally anyway. Might as well get this PR started.

[coveralls]

Coverage decreased (-0.2%) to 96.679% when pulling 9f70bd4 on shanecav84:rails_6 into ecc06f6 on smartinez87:master.

[shanecav84]

Changes so far:

• Support Rails 6.0.0.beta
• Removed coveralls until thor is updated because Rails 6 requires a higher version than coveralls allows
• Avoid the following deprecation warning for Rails version >= 6:

  DEPRECATION WARNING: `Module#parent_name` has been renamed to `module_parent_name`.
  `parent_name` is deprecated and will be removed in Rails 6.1.
  

[ansonhoyt]

Are you good folks still working on this? Looks like you made good progress, and now that Rails 6.0.0.rc1 is out, you should have a solid target to land this against.

[shanecav84]

I've updated rails to 6.0.0.rc1 and rebased on master.

[EmilioCristalli]

thanks for the update @shanecav84 ! is this still a WIP or you think it's ready?

[shanecav84]

I don’t think anything will need to change between now and an official Rails 6 release other than rebasing.

[axlekb]

Ready for update! :-)

[shanecav84]

Finally 😄

[shanecav84]

@smartinez87 You might want to change the gemspec https://github.com/shanecav84/exception_notification/commit/201c8bec0f86e332fbd6cc251e3fbf4075b0e26f