Add Latvian (lv) flavor with Latvian municipalities

110 municipalities and 9 republican cities.

Translations will come later.
Add Latvian (lv) postal code field (LV-XXXX)
Add Latvian (lv) personal code field (XXXXXX-XXXXX)
Merge pull request #70 from intgr/ee

Add Estonian (ee) flavor with zipcode, counties and personal ID code fields
Merge pull request #68 from intgr/lv

Add Latvian (lv) flavor: postal code, personal code and municipality fields
doc: Finland not Finnland
Merge pull request #71 from intgr/fi

doc: Finland not Finnland
Add test directory to $PYTHONPATH during tests

Fix for #49
Merge pull request #72 from django/issue-49

Add test directory to $PYTHONPATH during tests
Extended the documentation about how to run tests.
Updated test requirements.
Simplified tox and travis configuration.
Updated English source translation catalog.
Add gender/birthdate functions to Estonian ID code