Improve micro copy

ui/src/ifql/components/FuncList.tsx

@@ -48,7 +48,7 @@ const FuncList: SFC<Props> = ({
               />
             ))
           ) : (
-            <div className="ifql-func--item empty">No results</div>
+            <div className="ifql-func--item empty">No matches</div>
           )}
         </FancyScrollbar>
       </ul>

ui/src/shared/components/FuncSelectorInput.tsx

@@ -18,7 +18,7 @@ const FuncSelectorInput: SFC<Props> = ({
     className="form-control input-sm ifql-func--input"
     type="text"
     autoFocus={true}
-    placeholder="Add Function..."
+    placeholder="Add a Function..."
     spellCheck={false}
     onChange={onFilterChange}
     onKeyDown={onFilterKeyPress}