docs/website: update sponsors for FOSDEM

Simply a matter of updating the year, since it's again Google and Mind
for the FOSDEM2018 developer meeting.

Also add the 2017 sponsorship to the "Past sponsors" section.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

docs/website/sponsors.html

@@ -21,8 +21,8 @@
 	      <div class="col-sm-8">
 		<a href="http://www.google.com">Google</a> is
 		sponsoring
-		the <a href="http://elinux.org/Buildroot:DeveloperDaysFOSDEM2017">Buildroot
-		  Developers Meeting at FOSDEM 2017</a> in Brussels, by
+		the <a href="http://elinux.org/Buildroot:DeveloperDaysFOSDEM2018">Buildroot
+		  Developers Meeting at FOSDEM 2018</a> in Brussels, by
 		providing logistics for the meeting: a free meeting
 		room and lunch for the participants.
 	      </div>
@@ -39,8 +39,8 @@
 		</div>
 		<div class="col-sm-8">
 		  As it did in previous years, <a href="http://www.mind.be">Mind</a>
-		  is sponsoring the Monday night dinner at the <a href="http://elinux.org/Buildroot:DeveloperDaysFOSDEM2017">Buildroot
-		    Developers Meeting at FOSDEM 2017</a> in Brussels.
+		  is sponsoring the Monday night dinner at the <a href="http://elinux.org/Buildroot:DeveloperDaysFOSDEM2018">Buildroot
+		    Developers Meeting at FOSDEM 2018</a> in Brussels.
 		</div>
 	      </div>
 	    </div>
@@ -83,9 +83,9 @@
 	      <div class="col-sm-12">
 		<a href="http://www.mind.be">Mind</a> sponsored the
 		dinner of the FOSDEM 2014, 2015, 2016 and 2017
-		Developers Meeting (Brussels) and ELCE 2016 (Berlin),
-		the meeting room and the dinner for the ELCE 2014
-		Developers Meeting (Düsseldorf).
+		Developers Meeting (Brussels) and ELCE 2016 (Berlin)
+                and 2017 (Prague), and the meeting room and the dinner for
+                the ELCE 2014 Developers Meeting (Düsseldorf).
 	      </div>
 	    </div>
 	  </div>
@@ -101,8 +101,8 @@
 	      <div class="col-sm-12">
 		<p><a href="http://www.google.com">Google</a> provided
 		  the logistics for the FOSDEM 2013, FOSDEM 2014,
-		  FOSDEM 2015 and FOSDEM 2016 Developer Days in
-		  Brussels, Belgium.</p>
+		  FOSDEM 2015, FOSDEM 2016 and FOSDEM 2017 Developer Days
+		  in Brussels, Belgium.</p>
 	      </div>
 	    </div>
 	  </div>