feat: update pr templates, closes #696 (#699)

* feat: update pr templates, closes #696

* fix: move lint command to end of bullet

.github/ISSUE_TEMPLATE.md

+## 🎉 Description
+
+<!-- Briefly describe the issue you are experiencing (or the feature you want to see added to OpenZeppelin). Tell us what you were trying to do and what happened instead. **Remember, this is _not_ a place to ask for help debugging code; for that, we welcome you in the [OpenZeppelin Slack Channel](https://slack.openzeppelin.org/).** -->
 
 - [ ] 🐛 This is a bug report.
 - [ ] 📈 This is a feature request.
 
 <!-- Please check one of the above by placing an x in the box. -->
 
-Briefly describe the issue you are experiencing (or the feature you want to see added to OpenZeppelin). Tell us what you were trying to do and what happened instead. **Remember, this is _not_ a place to ask for help debugging code; for that, we welcome you in the [OpenZeppelin Slack Channel](https://slack.openzeppelin.org/).**
-
 ## 💻 Environment
 
-First, we need to know what your environment looks like.
+Next, we need to know what your environment looks like.
 
 - Which version of OpenZeppelin are you using?
 - What network are you deploying to? testrpc? Ganache? Ropsten?
@@ -29,4 +30,5 @@ insert short code snippets here
 <!-- If your code is larger, consider linking us to a repo illustrating your issue. -->
 
 ## 👍 Other Information
+
 <!-- List any other information that is relevant to your issue. Error logs, related issues, suggestions on how to fix, Stack Overflow links, forum links, etc. -->

.github/PULL_REQUEST_TEMPLATE.md

-<!-- 🎉 Thank you for submitting a PR! Before submitting, please review the following checklist: -->
+<!-- 0. 🎉 Thank you for submitting a PR! -->
 
-- [ ] 📘 I've reviewed the [OpenZeppelin Contributor Guidelines](/docs/CONTRIBUTING.md)
-- [ ] ✅ I've added tests where applicable to test my new functionality.
-- [ ] 📖 I've made sure that my contracts are well-documented.
-- [ ] 🎨 I've run the JS/Solidity linters (`npm run lint:all:fix`) and fixed any issues.
-
-<!-- **Does this close any open issues?** If so, list them here. -->
+<!-- 1. **Does this close any open issues?** If so, list them here. If not, remove the `Fixes #` line. -->
 
 Fixes #
 
----
-
 # 🚀 Description
 
-<!-- Describe the changes introduced in this pull request -->
-<!-- Include any context necessary for understanding the PR's purpose. -->
\ No newline at end of file
+<!-- 2. Describe the changes introduced in this pull request -->
+<!--    Include any context necessary for understanding the PR's purpose. -->
+
+<!-- 3. Before submitting, please review the following checklist: -->
+
+- [ ] 📘 I've reviewed the [OpenZeppelin Contributor Guidelines](/docs/CONTRIBUTING.md)
+- [ ] ✅ I've added tests where applicable to test my new functionality.
+- [ ] 📖 I've made sure that my contracts are well-documented.
+- [ ] 🎨 I've run the JS/Solidity linters and fixed any issues (`npm run lint:all:fix`).
\ No newline at end of file