fifc removes a file using a wrapping function instead of with rm

[halostatue]

In _fifc.fish:82, there is a bare rm … of the completion file generated. If you have a wrapping function (function rm; command grm --interactive --verbose $argv; end), this will be called, prompting for removal. Because the rm is in a completion function, there is no way to respond—and the completion file is not removed. This happens on every completion call (e.g., <Tab>).

This line should be command rm ….

[ollehu]

This PR #49 might solve this issue as well.