Apply GitHub default community health

* Remove `CODE_OF_CONDUCT.adoc` if favor of the same for a GitHub org
* Move `LICENSE.txt` to the root project dir
* Fix `build.gradle` to copy a `LICENSE.txt` from the actual location
* Fix `README.md` and `CONTRIBUTING.adoc` to point into the actual `CODE_OF_CONDUCT`
& Security policy
* Add `ISSUE_TEMPLATE` directory with files similar to ones in `spring-session`
* Fix wrong section `id` in the `whats-new.adoc`

.github/ISSUE_TEMPLATE.md

@@ -1,27 +0,0 @@
-<!--
-!!! To report Security Vulnerabilities, please go to https://pivotal.io/security !!!
--->
-**Affects Version(s):** \<Spring Integration version>
-
----
-<!--
-Thanks for raising a Spring Integration issue. What sort of issue are you raising?
-
-## Question
-
-Please ask questions about how to use something, or to understand why something isn't
-working as you expect it to, on
-[Stack Overflow using the `spring-integration` tag](https://stackoverflow.com/questions/tagged/spring-integration).
-
-## Bug report
-
-Please provide details of the problem, including the version of Spring Integration that you
-are using. If possible, please provide a test case or sample application that reproduces
-the problem. This makes it much easier for us to diagnose the problem and to verify that
-we have fixed it.
-
-## Enhancement
-
-Please start by describing the problem that you are trying to solve. There may already
-be a solution, or there may be a way to solve it that you hadn't considered.
--->

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,24 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: 'type: bug, status: waiting-for-triage'
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior.
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Sample**
+
+A link to a GitHub repository with a [minimal, reproducible sample](https://stackoverflow.com/help/minimal-reproducible-example).
+
+Reports that include a sample will take priority over reports that do not.
+At times, we may require a sample, so it is good to try and include a sample up front.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Community Support
+    url: https://stackoverflow.com/questions/tagged/spring-integration
+    about: Please ask and answer questions on StackOverflow with the tag spring-integration

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,25 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: 'status: waiting-for-triage, type: enhancement'
+assignees: ''
+
+---
+
+**Expected Behavior**
+
+<!--- Tell us how it should work -->
+
+**Current Behavior**
+
+<!--- Explain the difference from current behavior -->
+
+**Context**
+
+<!--- 
+How has this issue affected you?
+What are you trying to accomplish?
+What other alternatives have you considered?
+Are you aware of any workarounds?
+-->

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,5 +1,6 @@
 <!--
-Thanks for contributing to Spring Integration. Please provide a brief description of your pull-request and reference any related issue numbers (prefix references with #).
+Thanks for contributing to Spring Integration. 
+Please provide a brief description of your pull-request and reference any related issue numbers (prefix references with #).
 
 See the [Contributor Guidelines for more information](https://github.com/spring-projects/spring-integration/blob/master/CONTRIBUTING.adoc).
 -->