Handle multiple -f args as you'd expect.

most of the time in linting even small software projects is
used up on booting node over and over again.  a project with
14 modules and 2.4k lines of typescript code takes 3s with
this patch and 11.6s without.
update readme, help
make tslint happy
Merge pull request #176 from zerobuzz/check-many-files-via-cli

Check many files via cli