In the interest of not messing with colons in filenames (among other
characters), this function has been changed to only remove control
characters and convert '/' to '-'. In the future, this should be updated
to check the current filesystem and use the appropriate munging for it.
Ref: https://stackoverflow.com/a/35352640/540162
Setting the `LESS` environment variable overrides the defaults used by
core.pager, which are FRX. Because `-R` is set in .bash_profile, only
`-FX` need be provided to provide the same option coverage.
Jordan Atwood