Change qi::lit for qi::symbols for the sides parameter parser.

Refactor code :
 - Suppress StartSide Enum
 - Change Side Structure for Enum

Signed-off-by: FILLAU Jean-Maxime <jean-maxime.fillau@mapotempo.com>

unit_tests/mocks/mock_datafacade.hpp

@@ -146,9 +146,8 @@ class MockBaseDataFacade : public engine::datafacade::BaseDataFacade
     }
 
     std::pair<engine::PhantomNode, engine::PhantomNode>
-    NearestPhantomNodeWithAlternativeFromBigComponent(
-        const util::Coordinate /*input_coordinate*/,
-        const engine::SideValue /*side_value*/) const override
+    NearestPhantomNodeWithAlternativeFromBigComponent(const util::Coordinate /*input_coordinate*/,
+                                                      const engine::Side /*side*/) const override
     {
         return {};
     }