Whitespace cleanup
rpi_temp: remove unused variables (causing shellcheck failure)
rpi_temp: remove dependency on 'bc'
raspi_temp: improve quoting
Plugin-Gallery: Get better 2nd level headingsReview of category "system"
Category Tree: Reduce number of categories
Moved all Raspberry Pi plugins to a common raspberry-pi directory. Removed absolute path in raspi_temp to make the plugin work on Pidora.