beecut: exit if getop_long_only returns an error

beecut now exists if an unknown option was given or an argument was missing
bee-check: fix reading the CONTENT file and the filename handling

there were problems if a filename contains spaces

replacing the for loop and always quoting the arguments fixes this issue
bee-query: fix reading the CONTENT file and the filename handling

there were problems if a filename contains spaces

replacing the for loops and always quoting arguments fixes this issue