Gil obradors created es models - rebase

[benkonrath]

@gil-obradors This is a rebase of your PR (#357). The merges were too confusing to read and I want to cleanup and merge this PR in time for the 2.2 release.

Closes #357

[benkonrath]

@gil-obradors I've made a few changes your PR so that it can be included in the 2.2 release. Here's an overview:

• Reverted ES province change to Alaba (changed it back to Araba). According to wikipedia, the official name is "Araba / Álava" but this change needs be made in separate PR where we can have a discussion on the best choice for the name. https://en.wikipedia.org/wiki/%C3%81lava
• Removed spaces and dashes before saving identity card value to the database.
• Changed identity card field length to 9 (as per the card length without spaces).
• Added some tests for the model fields.

It would be great if you can look over the changes if you have time. I'm planning to merge this into master tomorrow. Thanks.

[codecov-io]

Codecov Report

Merging #372 into master will decrease coverage by 0.02%. The diff coverage is 92.59%.

@@            Coverage Diff             @@
##           master     #372      +/-   ##
==========================================
- Coverage   95.96%   95.94%   -0.03%     
==========================================
  Files         160      161       +1     
  Lines        4068     4095      +27     
  Branches      527      528       +1     
==========================================
+ Hits         3904     3929      +25     
- Misses         99      100       +1     
- Partials       65       66       +1

Impacted Files	Coverage Δ
localflavor/es/models.py	92.59% <92.59%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 0ff23bb...eb34207. Read the comment docs.