tests: added data file and test coverage to demonstrate encodings

[abramsimon]

The library uses fs.createReadStream to read files when fromFile is called and passes through options, including encoding, to the fs call. This is not obvious, resulting in issue #402. I have added a test to demonstrate this capability and a data file encoded in latin1 for use in the test.

Issue #402

[coveralls]

Pull Request Test Coverage Report for Build 241

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 95.702%

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Totals
Change from base Build 238:	0.3%
Covered Lines:	664
Relevant Lines:	681

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💛 - Coveralls