Add issue template (#208)

* Add issue template

* Fix issue template description

* Replace RTOS with OS

.github/ISSUE_TEMPLATE/general-issue.md

@@ -0,0 +1,24 @@
+---
+name: General issue
+about: General issue template for micro XRCE-DDS Agent
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+## Issue template
+
+- Hardware description: <!-- hardware where you are running the micro XRCE-DDS Agent -->
+- OS: <!-- OS where you are using the micro XRCE-DDS Agent -->
+- Installation type: <!-- CMake flags, FastDDS version, etc  -->
+- Version or commit hash: <!-- version or branch used to compile the micro XRCE-DDS Agent -->
+
+#### Steps to reproduce the issue
+<!-- Detailed instructions on how to reliably reproduce this issue http://sscce.org/-->
+
+#### Expected behavior
+
+#### Actual behavior
+
+#### Additional information