removed overkill import function. We don't need to search library paths etc, we know where our modules are.
more cleanups related to removal of import function
removed unused function getScriptAbsoluteDir
use .sh for scriptmodule extension as shinc is no standard (so editors can't guess syntax highlight by default).
split out package functions to packages.sh
split out emulators and libretro cores into separate module files - supplementary modules still to do
add functions for registering/loading the modules
split supplementary.sh into auto-loading modules
remove call to removed function registerFunctions
don't keep multiple associative arrays with module functions. We can determine them as needed.
change output of retropie_packages to show index and module id. since we are not hardcoding the index, it's possible they can change
so it will be a good idea to be able to use the module id
fixed emulationstation function naming
fixed xboxdrv function naming
use rps_checkNeededPackages for handling dependencies for depen_snes9x
simplify binaries installation code:
 - automatically install all depends, rather than a hardcoded list
 - use the textual id for installation, making it more readable than using the id and having to comment what each id is
 - don't hardcode the range of emulators to configure - configure all emulators and libretro cores
renamed the global associative arrays
add facility for rp_callFunction with only an index/module_id to call all script modes (depen / sources / build / configure etc)
use rp_callFunction directly for the binaries based installation which should be more efficient than continually sourcing the retropie_packages.sh script
renamed rp_callFunction to rp_callModule
added ensureRootdirExists to rps_main_binaries
use rp_callModule rather than calling retropie_packages.sh directly
improved usage info wording
Merge pull request #391 from joolswills/re-organisation

Re organisation (separate emulators into modules)