Add issue template

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,22 @@
+#### System information
+
+Monero version: `monerod --version` or commit hash via `git rev-parse --short HEAD` if `master` branch
+
+Stratum commit hash: `git rev-parse --short HEAD`
+
+OS & Version: Linux/OSX
+
+#### Expected behaviour
+
+
+#### Actual behaviour
+
+
+#### Steps to reproduce the behaviour
+
+
+#### Backtrace
+
+````
+[backtrace]
+````