-Added default plugins to mupen64plus.conf file:
-Gfx: ricevideo.so
-Audio: mupen64_audio.so
-Input: blight_input.so
-RSP: mupen64_hle_rsp_azimer.so
These two fixes address the problem of no plugins being selected on first load of mupen64plus.
-Modified Makefile so 'make install' will copy default config files to install dir
-Modified gui_gtk/rombrowser.c so rombrowser.cache file is saved to user config dir.
-Modified main/main.c so on creation of user config dir ~/.mupen64plus, all config files from install dir are copied to user config dir.