Add Faker::NHS - Support for the British National Health Service

[maxehmookau]

Every person in the United Kingdom has a unique code which identifies them to the National Health Service (NHS). The code is in XXX XXX XXXX format where the final digit is a check digit calculated from the previous ones.

More information on NHS numbers can be found here: https://en.wikipedia.org/wiki/NHS_number

This commit adds the Faker::NHS class along with the Faker::NHS.nhs_number method to generate a valid NHS number.

[suezhou]

It would be very nice to have nhs number included!

[vbrazo]

Overall looks good. Don't forget to add documentation next time. Thanks for contributing 🥇

[vbrazo]

@maxehmookau Travis is red because of this test:

      8:   def test_nhs_british_number
      9:     sample = @tester.british_number
  => 10:     assert sample.length == 12
     11:     assert_equal ' ', sample[3]
     12:     assert_equal ' ', sample[7]
     13:     assert sample[0..2].split.map { :to_i }.all? { :is_digit? }

It seems that your algorithm fails when we run the tests in ruby 2.1.10 and 2.2.10 because it generates 13 characters instead of 12. Could you take a look at this issue and circle back with me?

[maxehmookau]

@vbrazo thanks for adding some basic docs!

That's very strange, glad you had CI running to catch that. I'll load up the older ruby version and try and resolve those failures soon.

[vbrazo]

No problem. I tested in the older versions and what I noticed was that it fails because the last digit that is being generated is 10 or 11, that's why we get 13 characters.

[vbrazo]

@maxehmookau just a quick update: this commit removes 2.1.10 and 2.2.10.