misc: github issue template.

Author: veox

.github/issue_template.md

@@ -0,0 +1,29 @@
+### Versions
+
+```
+OS:       
+Python:   
+krakenex: 
+```
+
+### What are you trying to achieve?
+
+
+
+``` python
+# code sample
+
+```
+
+### What do you expect to happen?
+
+
+
+### What happens instead?
+
+
+
+``` python
+# error message
+
+```