Announce instruction on mode change

[TheMarex]

Instructions need to be announced on mode change, even if the way name is the same.

Example: http://map.project-osrm.org/?hl=en&loc=-18.277037,21.788029&loc=-18.272243,21.793947&z=15&center=-18.277535,21.782681&alt=0&df=0&re=0&ly=-1171809665

curl "http://router.project-osrm.org/viaroute?loc=-18.277037,21.788029&loc=-18.272243,21.793947&instructions=true"

{"hint_data":{"locations":["XxWyA9gowAMAAAAAEwAAAAAAAAA0AQAAPQAAAH7ZYQYAAAAAUx3p_np1TAEEABEA","wCjAA831DAwAAAAABAAAAAsAAAAvAAAA1xAAAJqA_gIAAAAACzDp_puMTAEEABEA"],"checksum":3879459955},"route_name":["",""],"via_indices":[0,23],"found_alternative":false,"route_summary":{"end_point":"","start_point":"","total_time":198,"total_distance":913},"via_points":[[-18.277037,21.788027],[-18.272243,21.793947]],"route_instructions":[["10","",73,0,39,"73m","N",0,1],["1","",839,3,187,"839m","N",352,2],["15","",0,22,0,"0m","N",0]],"route_geometry":"xipza@svyph@yUTeHC}Gy@uE^wJ`GeIhBiDRcGuByNaPgQ}_@me@}v@gz@m|Aq[u_AyOei@iI}PuF{HmMmHyAuAo@aC]cFa@oPSgB","status_message":"Found route between points","status":0}