As developer of the Nutrition Information API, I want to use TypeScript

As developer of the Nutrition Information API, I want to use TypeScript, so I get:

To play around with TypeScript
Class and Module Support
Static Type-checking
ES6 Feature Support
Syntax Similarity to C# and Java
Superset of JavaScript

Acceptance Criteria Do not lose any current functionality, i.e. after moving to TypeScript, the following stories should not regress:

5 As a contributor to the Nutrition Information API, I want continuous integration to automatically build, unit test, and integration test each commit for a pull request, so I can detect errors early through automation.
14 As a contributor to the Nutrition Information API, I want continuous integration to automatically check ~100% code coverage for unit tests of a pull request, so I can automatically assert there have been automated unit tests written for all of the new code.

Test Plan Test #14 by following the same test steps but locally, i.e. running npm test and checking the result of the command. Then test #5 by confirming the Travis CI check is performed on the Pull Request.

Development Work Change to typescript by doing the following:

Add dev dependency typescript 2.X
Add dev dependency ts-node
- Must be less than 1.3.0 and create an issue to update the ts-node version once the following is resolved:
- https://github.com/TypeStrong/ts-node/issues/183
- https://github.com/istanbuljs/istanbul-lib-hook/issues/7
- https://github.com/istanbuljs/istanbul-lib-hook/pull/8
Update istanbul version to 1.X
Add @types dev dependencies for mocha, istanbul, chai, node
Update ./package.json test script's mocha options to include ts-node/register
Update ./test/index.js to be a typescript file
Update ./index.js to be a typescript file
Add a build script to ./package.json, which would be "tsc" and build to a bin directory
- This will require a ./tsconfig.json file for compiler options

Definition of Ready

[x] Value for stakeholder identified
[x] Acceptance criteria identified
[x] Test plan identified
[x] Development work identified
[N/A] Documentation work identified
[N/A] Story is sliced vertically

NutritionMate / Nutrition.Information.Api

As developer of the Nutrition Information API, I want to use TypeScript #19

5 As a contributor to the Nutrition Information API, I want continuous integration to automatically build, unit test, and integration test each commit for a pull request, so I can detect errors early through automation.

14 As a contributor to the Nutrition Information API, I want continuous integration to automatically check ~100% code coverage for unit tests of a pull request, so I can automatically assert there have been automated unit tests written for all of the new code.