build core, basic and go variants and add template

go/nvim/luasnippets/go.lua

@@ -0,0 +1,10 @@
+return {
+  parse(
+    { trig = 'func', name = 'Function' },
+    'func ${1:name}($2) $3{\n\t$4\n}'
+  ),
+  parse(
+    { trig = 'err', name = 'Handle error' },
+    'if ${2:err} != nil { return ${1}${2} }'
+  ),
+}