Adding ISSUE_TEMPLATE (#21)

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,20 @@
+### System information (version)
+
+* Operating System / Platform => ❔
+* OpenCV => ❔
+* Ceres => ❔
+* Boost => ❔
+* C++ => ❔
+* Compiler => ❔
+
+### Vision system
+
+* Number of cameras => ❔
+* Types of cameras => ❔ (perspective, fisheye, hybrid)
+* Multicamera configurations => ❔ (overlapping, non-overlapping, converging)
+* Configuration file => ❔ (i.e. `*.yml`)
+* Image sequences => ❔ (if relevant and possible, please share image sequences)
+
+### Describe the issue / bug
+
+Please provide a clear and concise description of what the issue / bug is.