Add Python install helper
Add Python install helper

Add a CMake function to our exported utilities to install Python files.
Specifically, this picks a reasonable default DESTINATION and preserves
subdirectory components of files to be installed.

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