Ensure clearing the cache always yields a new list

[ryuslash]

Hi,

By using the list function we ensure we don't reuse the same value like when using a quoted list literal.

While I was working on my previous patches I noticed that the fiplr-clear-cache function only cleared the cache the first time I called it. This seems to have something to do with the fact that a quoted list is used to clear it. Instead of setting the *fiplr-caches* to a fresh new list it keeps setting it to the same list, which has since been populated with data.

1. Use fiplr-find-file to populate the cache.
2. Inspect *fiplr-caches*, it should be filled with data.
3. Call fiplr-clear-cache and check that *fiplr-caches* is now empty.
4. Repeat steps 1-3, but notice that this time the *fiplr-caches* variable is not empty.

I tried this on both the Emacs trunk version and Emacs 24.3.

Please let me know what you think.

[d11wtq]

Oh, that's a really good catch, thank you!

[ryuslash]

Thanks!