For compiling together files which use the Gravity in-file commands
-r / --root > root file
-o / --output > output file
-v / --verbose > verbose mode
--help > prints the help text
include > a straightforward file-into-file text assembler, eg. {{include:aFile.txt}}
gravity -r project/mainFile.txt -o build/output.txt
gravity --root project/mainFile.txt --output build/output.tx --verbose
gravity --help