More specific empty state message wording

I've changed all the instances of "Nothing to show here" to specifically mention
the name of the entity of which there are none to show. This makes for a
slightly smoother reading experience.

app/views/projects/issues/_issues.html.haml

@@ -83,7 +83,7 @@
     = render @issues
     - if @issues.blank?
       %li
-        %h4.nothing_here_message Nothing to show here
+        %h4.nothing_here_message No issues to show
 - if @issues.present?
   .pull-right

app/views/projects/merge_requests/index.html.haml

@@ -65,7 +65,7 @@
         = render @merge_requests
         - if @merge_requests.blank?
           %li
-            %h4.nothing_here_message Nothing to show here
+            %h4.nothing_here_message No merge requests to show
     - if @merge_requests.present?
       .pull-right
         %span.cgray.pull-right #{@merge_requests.total_count} merge requests for this filter

app/views/projects/milestones/index.html.haml

@@ -26,6 +26,6 @@
           - if @milestones.blank?
             %li
-              %h3.nothing_here_message Nothing to show here
+              %h3.nothing_here_message No milestones to show
       = paginate @milestones, theme: "gitlab"

app/views/shared/_issues.html.haml

@@ -11,5 +11,5 @@
           = render 'projects/issues/issue', issue: issue
   = paginate @issues, theme: "gitlab"
 - else
-  %p.nothing_here_message Nothing to show here
+  %p.nothing_here_message No issues to show

app/views/shared/_merge_requests.html.haml

@@ -10,4 +10,4 @@
   = paginate @merge_requests, theme: "gitlab"
 - else
-  %h3.nothing_here_message Nothing to show here
+  %h3.nothing_here_message No merge requests to show