* Refactor to use CodeGenerator interface.
- Move code to its own header file to be included in flatc_main.cpp
- Refactor code to use CodeGenerator interface for all languages
* Format all files
* remove lua code generator since it doesn't support bfbs generator
* Update CMakeLists file with new idl_gen_*.cpp and idl_gen_*.h files
* Add idl_gen_swift header file
* Add idl_gen_swift header file and update bazel file
* Remove CodeGenerator interface for idl_gen_text.*. Remove comments and extern declaration
* Reorder header and implementation files in CMakeLists.txt
* Add idl_gen_* header files to implementation files
* Update CMakeLists and remove unused import
Co-authored-by: Derek Bailey <derekbailey@google.com>