feat(render): add new query capabilities for improved tests (testing-…

…library#17)

**What**: Add the following methods

- queryByText
- getByText
- queryByPlaceholderText
- getByPlaceholderText
- queryByLabelText
- getByLabelText

**Why**: Closes testing-library#16

These will really improve the usability of this module. These also align much better with the guiding principles 👍

**How**:

- Created a `queries.js` file where we have all the logic for the queries and their associated getter functions
- Migrate tests where it makes sense
- Update docs considerably.

**Checklist**:

* [x] Documentation
* [x] Tests
* [x] Ready to be merged <!-- In your opinion, is this ready to be merged as soon as it's reviewed? -->
* [ ] Added myself to contributors table N/A

feat(node): relax Node version requirement to >= 6 (testing-library#14)

feat: Add getByTestId utility (testing-library#10)

* feat: Add getByTestId utility

* Updates to getByTestId documentation

* minor tweaks

feat(typings): add ts definitions (testing-library#7)

* feat(typings): add ts definitions

* chore(contributors): add myself

fix(TypeScript): add missing 'typings' folder to files property (test…

…ing-library#9)

feat(typings): add ts definitions (testing-library#7)

* feat(typings): add ts definitions

* chore(contributors): add myself

feat(unmount): add `unmount` to render object

fix(sel): match react native web's testID prop

Closes testing-library#1

fix(release): manually release a major version

There was an issue with a major release, so this manual-releases.md
change is to release a new major version.

BREAKING CHANGE: release 1.0.0

feat: initial release