Update .gitignore

.gitignore

@@ -1,3 +1,18 @@
+# gitginore template for creating Snap packages
+# website: https://snapcraft.io/
+
+parts/
+prime/
+stage/
+*.snap
+
+# Snapcraft global state tracking data(automatically generated)
+# https://forum.snapcraft.io/t/location-to-save-global-state/768
+/snap/.snapcraft/
+
+# Source archive packed by `snapcraft cleanbuild` before pushing to the LXD container
+/*_source.tar.bz2
+
 # Prerequisites
 *.d