Show information message to indicate filtered results

- When the explore results are filtered(so no user query + default
sorting), show a information message to indicate it has been filtered.
Also offer users a easy way to unfilter the results.

Author: Gusted

options/locale/locale_en-US.ini

@@ -275,6 +275,9 @@ org_no_results = No matching organizations found.
 code_no_results = No source code matching your search term found.
 code_search_results = Search results for '%s'
 code_last_indexed_at = Last indexed %s
+relevant_repositories_tooltip = Repositories that are forks or don't have a topic and description aren't being shown.
+relevant_repositories = Only relevant repositories are being shown, <a href="%s">show unfiltered results</a>.
+
 
 [auth]
 create_new_account = Register Account

routers/web/explore/repo.go

@@ -73,7 +73,7 @@ func RenderRepoSearch(ctx *context.Context, opts *RepoSearchOptions) {
 	default:
 		ctx.Data["SortType"] = "recentupdate"
 		orderBy = db.SearchOrderByRecentUpdated
-		onlyShowRelevant = true
+		onlyShowRelevant = !ctx.FormBool("no_filter")
 	}
 
 	keyword := ctx.FormTrim("q")

templates/explore/repo_search.tmpl

@@ -30,4 +30,9 @@
 		<button class="ui blue button">{{.i18n.Tr "explore.search"}}</button>
 	</div>
 </form>
+{{if .OnlyShowRelevant}}
+  <div class="ui blue attached message" style="max-width: 90%; margin-top: 0; border-top: 0">
+    <span class="ui tooltip" data-content="{{.i18n.Tr "explore.relevant_repositories_tooltip"}}">{{.i18n.Tr "explore.relevant_repositories" ((printf "%s%s" $.Link "?no_filter=1")|Escape) | Safe}}</span>
+  </div>
+{{end}}
 <div class="ui divider"></div>