Go to above link then search for "Microchip Gallery". Click on "Download" on left side of screen and run the downloaded file (if Atmel Studio was opened when you did this, close and reopen Atmel Studio). This should now allow Atmel Studio access to plugins (TOOLS | Extensions and Updates). It is suggested in go ahead and install "Terminal for Atmel Studio"
To get printf to work with floating point values:
Project | nameofproject Properties | Toolchain : AVR/GNU Linker | General | Check "Use vprintf library(-Wl,-u,vfprintf)"
Project | nameofproject Properties | Toolchain : AVR/GNU Linker | Miscellaneous | Other Linker Flags put into textbox | "-lprintf_flt" (leave off quotes).