initial commit

This is the revised Carteret logger that incorporates an SD card, RTC
and float switch. Let it be know that the confusing valve names have
also been done away with.
verified code for Carteret Field deployment oflogger

changed log file name
added comment/uncomment section for each site timing variables
tested hardware
changed valve names to something more immediately meaningfull
worried about evaluation order in millis() timing while loops. added
lots of parentheses
tried to fix log file header printing, running into issues with printing
last element (temp)
TODO: fix that