Vue.js/.github/PULL_REQUEST_TEMPLATE.md

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Please make sure to read the Pull Request Guidelines:
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**What kind of change does this PR introduce?** (check at least one)

- [ ] Bugfix
- [ ] Feature
- [ ] Code style update
- [ ] Refactor
- [ ] Build-related changes
- [ ] Other, please describe:

**Does this PR introduce a breaking change?** (check one)

- [ ] Yes
- [ ] No

If yes, please describe the impact and migration path for existing applications:

**The PR fulfills these requirements:**

- [ ] It's submitted to the `dev` branch for v2.x (or to a previous version branch), _not_ the `master` branch
- [ ] When resolving a specific issue, it's referenced in the PR's title (e.g. `fix #xxx[,#xxx]`, where "xxx" is the issue number)
- [ ] All tests are passing: https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#development-setup
- [ ] New/updated tests are included

If adding a **new feature**, the PR's description includes:
- [ ] A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

**Other information:**
move md files into hidden directory 8 years ago			`<!--`
			`Please make sure to read the Pull Request Guidelines:`
			`https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#pull-request-guidelines`
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Issue template example (#5073) 8 years ago
Reorganize and update PR template (#5106) * Reorganize and update PR template * Update PULL_REQUEST_TEMPLATE.md * Remove required info for bugfixes 8 years ago			`<!-- PULL REQUEST TEMPLATE -->`
			`<!-- (Update "[ ]" to "[x]" to check a box) -->`

			`What kind of change does this PR introduce? (check at least one)`

			`- [ ] Bugfix`
			`- [ ] Feature`
			`- [ ] Code style update`
			`- [ ] Refactor`
			`- [ ] Build-related changes`
			`- [ ] Other, please describe:`

			`Does this PR introduce a breaking change? (check one)`

			`- [ ] Yes`
			`- [ ] No`

			`If yes, please describe the impact and migration path for existing applications:`

			`The PR fulfills these requirements:`

			- [ ] It's submitted to the `dev` branch for v2.x (or to a previous version branch), _not_ the `master` branch
			- [ ] When resolving a specific issue, it's referenced in the PR's title (e.g. `fix #xxx[,#xxx]`, where "xxx" is the issue number)
			`- [ ] All tests are passing: https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#development-setup`
			`- [ ] New/updated tests are included`

			`If adding a new feature, the PR's description includes:`
			`- [ ] A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)`

			`Other information:`