add book «Everyday Rails Testing with RSpec» to Further Reading

It's good for reading. I recommend it.
Add license information
Merge pull request #61 from stamm/master

Add book «Everyday Rails Testing with RSpec» to Further Reading
Update README.md

Probably intended to mean the opposite.
Merge pull request #63 from nigel-lowry/master

Small typo.
Prefer %w to the literal array syntax when you need an array of strings.

https://github.com/bbatsov/ruby-style-guide#collections
Merge pull request #64 from kbighorse/master

Prefer %w to the literal array syntax when you need an array of strings.
SQL Injection teachers

[ruby regular expressions](https://github.com/bbatsov/ruby-style-guide#regular-expressions)

```ruby
string = "some injection\nusername"
string[/^username$/]   # matches
string[/\Ausername\z/] # don't match
```
Merge pull request #66 from artemeff/patch-1

SQL Injection teachers
Merge pull request #6 from bbatsov/master

Update