Area support

[phibos]

Issue type

• Feature

Summary

I have created a new PR to merge it with the latest master and add some additional tests. You can find more about the original PR here #24

The original description is

I've added Area functionality, since I need it in my project.

I have no idea what am I doing, since I'm working with overpass API for like a day.
No tests included (sorry), but general usage for finding areas works for my purpose.

Please add tests.

references: #19

[coveralls]

Coverage decreased (-7.7%) to 86.451% when pulling 4a9ce42 on area_support into 2961bb9 on master.

[coveralls]

Coverage decreased (-0.8%) to 93.373% when pulling 38848f9 on area_support into 2961bb9 on master.

[coveralls]

Coverage decreased (-0.7%) to 93.52% when pulling 7efdae7 on area_support into 2961bb9 on master.