Added small note about usage of lib api macros.
Added exported .cmake file to .gitignore.
Updated lib/CMakeLists.txt.

- Lib is getting runtime functions, so it is now a real lib.
- The lib now exports a .cmake file that other projects can include to get
a formal cmake dep on the project.
Added dipstick/meta.hpp as an example of how to use lib-api.hpp.
Added dipstick/meta.hpp to define its API macros.
Static builds now define import/export macros to be empty.
Added missing 'defined' keyword.
Small whitespace change.
Added explicit versioning, versioned compiler.