main: revamped command-line parsing infrastructure.
main: added environment helper functions.
main: updated README file to reflect changes in building and execution.
main: removed extra semicolons in bit operation function declarations.
main: fixed a potential issue in machine_deinit.
main: log callback function can now be overriden.
main: XML input configuration support is now optional.
main: softened link between video and input frontends.
libretro: added libretro-test sample code.
libretro: stripped down libretro-test code.
libretro: renamed library.
libretro: libretro core can now be built and packaged as part of Emux.
libretro: added basic Emux integration along with logging support.
main: removed warnings occuring when compiling using -std=gnu99.
libretro: environment callback can now be accessed externally.
main: clock ticking delay handling is now optional.
main: machines can now be stepped.
main: command line parameters can now be set at compile-time.
libretro: all modules are now compiled as part of the core.