Fixed connection errors.

[ferluci]

Previously, any connection errors caused the entire library to crash. Now such errors are caught.

[coveralls]

Pull Request Test Coverage Report for Build 32

• 17 of 19 (89.47%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.3%) to 99.694%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
proxyscrape/scrapers.py	16	18	88.89%
<!--	Total:	17	19	89.47%	-->

Totals
Change from base Build 30:	-0.3%
Covered Lines:	474
Relevant Lines:	476

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 35

• 24 of 24 (100.0%) changed or added relevant lines in 4 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 33:	0.0%
Covered Lines:	474
Relevant Lines:	474

---

💛 - Coveralls

[JaredLGillespie]

Made a few tiny changes so it could be used with the proxyscrape.com integration and added a few tests.

Thanks for the PR :smile: