docs: add spellcheck to 'make docs' sphinx docs

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  writing output... [ 21%] events/Summits/OpensourceSummit...
  writing output... [ 22%] events/Summits/UKNO/2017_04_30_...

  featuresbyrelease/vpp16.06.rst:34:Rasberry:vpp16.06
  writing output... [100%] usecases/vppinazure
  Spelling checker messages written to /vpp/docs/_build/html/output.txt

  Warning, treated as error:
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  make[1]: *** [html] Error 2
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Type: feature

Change-Id: Id49be4fbee617f544f1ab8e78e7de8a4df36448b
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>

2 files changed, 3 insertions, 3 deletions

diff --git a/docs/gettingstarted/developers/fib20/routes.rst b/docs/gettingstarted/developers/fib20/routes.rst
index 464a24af5d3..1ee09ced448 100644
--- a/docs/gettingstarted/developers/fib20/routes.rst
+++ b/docs/gettingstarted/developers/fib20/routes.rst
@@ -27,7 +27,7 @@ The route data is decomposed into three parts; entry, path-list and paths;
 
     * Attached next-hop: the path is described with an interface and a next-hop. The next-hop is in the same sub-net as the router's own address on that interface, hence the peer is considered to be *attached*
 
-    * Attached: the path is described only by an interface. All address covered by the prefix are on the same L2 segment to which that router's interface is attached. This means it is possible to ARP for any address covered by the prefix Рwhich is usually not the case (hence the proxy ARP debacle in IOS). An attached path is only appropriate for a point-to-point (P2P) interface where ARP is not required, i.e. a GRE tunnel.
+    * Attached: the path is described only by an interface. All address covered by the prefix are on the same L2 segment to which that router's interface is attached. This means it is possible to ARP for any address covered by the prefix which is usually not the case (hence the proxy ARP debacle in IOS). An attached path is only appropriate for a point-to-point (P2P) interface where ARP is not required, i.e. a GRE tunnel.
 
     * Recursive: The path is described only via the next-hop and table-id. 
 
@@ -132,7 +132,7 @@ is attached are installed in forwarding. This requires the use of *cover trackin
 where a route maintains a dependency relationship with the route that is its less
 specific cover. When this cover changes (i.e. there is a new covering route) or the
 forwarding information of the cover is updated, then the covered route is notified.
-Adj-fibs that fail this cover check are not installed in the fib_table_tճ forwarding
+Adj-fibs that fail this cover check are not installed in the fib_table_t's forwarding
 table, there are only present in the non-forwarding table.
 
 Overlapping sub-nets are not supported, so no adj-fib has multiple paths. The control
diff --git a/docs/gettingstarted/developers/fib20/tunnels.rst b/docs/gettingstarted/developers/fib20/tunnels.rst
index 1613a69df8c..c33d63c3b92 100644
--- a/docs/gettingstarted/developers/fib20/tunnels.rst
+++ b/docs/gettingstarted/developers/fib20/tunnels.rst
@@ -18,7 +18,7 @@ Figure 11 shows the control plane object graph for a route via a tunnel. The two
 sub-graphs for the route via the tunnel and the route for the tunnel's
 destination are shown to the right and left respectively. The red line shows the
 relationship form by stacking the two sub-graphs. The adjacency on the tunnel
-interface is termed a ԭid-chainՠthis it is now present in the middle of the
+interface is termed a 'mid-chain' this it is now present in the middle of the
 graph/chain rather than its usual terminal location.
 
 The mid-chain adjacency is contributed by the gre_tunnel_t , which also becomes