title: Change a single route parameter on the current route in Angular 2
body: <p>Is it possible to change a single route parameter in the current route, while keeping all the other parameters?
  This is for use in a paging component, which will route to a new page while keeping the other parts of the current route the same.</p>
  
  <p>Some examples:</p>
  
  <ul>
  <li>Default page to page 2: <code>orders?foo=foo&amp;bar=bar</code> > <code>orders?foo=foo&amp;bar=bar&amp;page=2</code></li>
  <li>Default page to page 2 (child): <code>orders/;foo=foo;bar=bar</code> > <code>orders/;foo=foo;bar=bar;page=2</code></li>
  <li>Page 2 to 3 on child and parent with parameters: <code>orders/;foo=foo;page=2?bar=bar</code> > <code>orders/;foo=foo;page=3?bar=bar</code></li>
  </ul>
  
  <p>I have tried using a <code>routerLink</code>, however this loses any additional parameters that are not originally part of the router link.</p>
  
  <p>I have also tried using the current <code>Router</code> to get an <code>Instruction</code> for the current path, however changing the parameters of the <code>Instruction</code> does not seem to have any effect when calling <code>navigateByInstruction()</code>.</p>