Fix some syntax errors in README.md

[ci skip]

Fixes #97
destroy! now once again calls destroy

This is because destroy! is called by :dependent => :destroy association definitions (yes, destroy! and not destroy), which means that associated records of a paranoid object would suddenly go missing... making it very hard to restore them!

So instead, it's now called really_destroy! and destroy! is just an alias for destroy once again
Merge pull request #98 from radar/really-destroy

destroy! now once again calls destroy
Relation doesn't have a default_scoped attr anymore

As of https://github.com/rails/rails/commit/94924dc32baf78f13e289172534c2e71c9c8cade
Tweak test setup to run on activerecord 4.1.0 as well
Remove duplicated ParentModel in test file
Override activerecord destroy!

As of https://github.com/rails/rails/commit/5aab0c053832ded70a3a4b58cb97f8f8bba796ba
that is the method called when destroying associated records.

Example: Both Article and Comment models acts_as_paranoid. Once an
article is destroyed it's expected that all of its comments are
destroyed the same way by only touching the deleted_at column rather
than permanently removing the object from the database.
Run travis build on both rails 4.0 and 4.1
Add test for destroying records in Rails 4.1
Use new alias really_destroy! on test example