Questions containing fractions should return fraction result

# Goodie Pull Request Template

Using this template will help us better understand your Instant Answer and assist you when necessary.  Simply copy and paste the markdown below into the description of your GitHub pull request and complete as appropriate.

**What does your Instant Answer do?**
Returns a fraction math result if the query contains fractions

**What problem does your Instant Answer solve (Why is it better than organic links)?**
Currently the calculator only returns decimal answers, this feature adds the answer in fraction form

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N/A

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**What are some example queries that trigger this Instant Answer?**
"3/7 + 5/6", "1/4 + 2/4";

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Anyone who has the need for a calculator

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Yes

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## Checklist
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```
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    Appended tests to the existing Calculator.t
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        [] Google Chrome
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```

@munizas will this ever "up-convert" a decimal to the fraction format? Personally I'd probably prefer that it didn't introduce artificial accuracy around numbers that are provided as decimals, what are your thoughts on this?