Allow options to be combined in grep #152
Description
Currently -v and -C are separate commands:
!hep grep
grep <pattern> <list> # filters the items in <list> by <pattern>
grep -C <n> <pattern> <list> # filter items in <list> by <pattern> and include <n> items before and after each matched item
grep -v <pattern> <list> # filter items in <list> not matching <pattern>
But we should be able to combine flags in a single command, more like:
grep [-C n] [-v] <pattern> <list>