Add Contributing Guidelines and Issue and Pull Request Template

Details

<p dir="auto">Before there was no contributing guidelines in Open food facts server repository. Seeing this I thought of adding it to the repository. It was highly appreciated by the owner of the repository and maintainers of the repository. <h4>Components <p dir="auto">The contributing guidelines are given below- <blockquote> <h1>Join the development <ul> <li>Before you join development, please set up the project on your local machine, run it and go through >the application completely. Press on any button you can find and see where it leads to. Explore.You'll >be more familiar with what is where and might even get some cool ideas on how to improve various >aspects of the app. <li>If you would like to work on an issue, drop in a comment at the issue. If it is already assigned to >someone, but there is no sign of any work being done, please free to drop in a comment so that the >issue can be assigned to you if the previous assignee has dropped it entirely. <h1>Contributing <p dir="auto">When contributing to this repository, please first discuss the change you wish to make via issue, or >the official <a href="https://slack-ssl-openfoodfacts.herokuapp.com/" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">slack channel. <h2>Pull Request Process <ol> <li>Ensure any install or build dependencies are removed before the end of the layer when doing a<br /> build. <li>Check that there are no conflicts and your request passes <a href="https://travis-ci.org" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">Travis build. >Check the log of the pass test if it fails the build. <li>Give the description of the issue that you want to resolve in the pull request message. The format >of the commit message to be fixed - <strong>Fixes #[issue number] [Description of the issue] Example: ><strong>Fixes #529: Add toast warning in <code>MainActivity.java <li>Wait for the maintainers to review your pull request and do the changes if requested. <h2>Contributions Best Practices <h3>Commits <ul> <li>Write clear meaningful git commit messages (Do read <a href="http://chris.beams.io/posts/git->commit/" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">here) <li>Make sure your PR's description contains GitHub's special keyword references that automatically >close the related issue when the PR is merged. (For more info click <a href="https://>https://github.com/blog/1506-closing-issues-via-pull-requests" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">here) <li>When you make very very minor changes to a PR of yours (like for example fixing a failing Travis >build or some small style corrections or minor changes requested by reviewers) make sure you >squash your commits afterward so that you don't have an absurd number of commits for a very small >fix. (Learn how to squash at <a href="https://davidwalsh.name/squash-commits-git" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">here <li>When you're submitting a PR for a UI-related issue, it would be really awesome if you add a >screenshot of your change or a link to a deployment where it can be tested out along with your PR. It >makes it very easy for the reviewers and you'll also get reviews quicker. <h3>Feature Requests and Bug Reports <ul> <li><span>When you file a feature request or when you are submitting a bug report to the [issue tracker]>(<a href="https://github.com/openfoodfacts/openfoodfacts-server/issues" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">https://github.com/openfoodfacts/openfoodfacts-server/issues), make sure you add steps to >reproduce it. Especially if that bug is some weird/rare one. <h4>Links <p dir="auto">You can see the changes in this pull request-<br /><span> <a href="https://github.com/openfoodfacts/openfoodfacts-server/pull/1113/files" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">https://github.com/openfoodfacts/openfoodfacts-server/pull/1113/files <p dir="auto"><br /><hr /><em>Posted on <a href="https://utopian.io/utopian-io/@ms10398/add-contributing-guidelines-and-issue-and-pull-request-template" target="_blank" rel="noreferrer noopener" title="This link will take you away from hive.blog" class="external_link">Utopian.io - Rewarding Open Source Contributors<hr /><p>