Error Importing due to missing extension.

[meirm]

Add missing .shp extention to plots/world.py:15, without it, astetik fails to load.

[pep8speaks]

Hello @meirm! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file astetik/plots/world.py:

Line 16:80: E501 line too long (99 > 79 characters)

[meirm]

Please review this fix, it is the only way it worked for me.