Show visibility (#1945)

docs/contract.hbs

@@ -50,7 +50,7 @@
 {{#ownFunctions}}
 [.contract-item]
 [[{{anchor}}]]
-==== `{{name}}({{args}}){{#if outputs}} → {{outputs}}{{/if}}`
+==== `{{name}}({{args}}){{#if outputs}} → {{outputs}}{{/if}}` [.visibility]#{{visibility}}#
 
 {{natspec.devdoc}}