This change introduces the ability to use the tilde (`~`) character in your
`-c/--config` flag value to expand your home directory. If invoking this via the
command line with `--config ~/.golangci-lint.yaml`, the user's shell expands the
`~` to the home directory. However, if something is invoking the program for
you (like an editor) it may not do the expansion.
Fixes#289
Signed-off-by: Tim Heckman <t@heckman.io>
