Update CMake tutorial
Update CMake tutorial

Update the CMake tutorial to cover export decoration of the C bindings
library.

lcm-proj/lcm,adeschamps/lcm,adeschamps/lcm,lcm-proj/lcm,bluesquall/lcm,bluesquall/lcm,lcm-proj/lcm,adeschamps/lcm,adeschamps/lcm,bluesquall/lcm,adeschamps/lcm,lcm-proj/lcm,lcm-proj/lcm,bluesquall/lcm,bluesquall/lcm,lcm-proj/lcm,lcm-proj/lcm,lcm-proj/lcm,adeschamps/lcm,bluesquall/lcm,adeschamps/lcm,bluesquall/lcm,adeschamps/lcm