LCSort returns nil for a number of catalog id numbers

[carolyncole]

@mzelesky & @tampakis I believe that this is a combination of bad data in voyager, but it could also be that lcsort is being too strict.

I retrieve a list of all items that reside in the Firestone library, to work on the locator code. It was suggested I use this gem to make the call numbers sortable. Unfortunately it returned nil for about 4k records that seem lc like to me. lsort_nil.txt

I added some code to my calling to parse these records, but I wanted to make you aware that there could either be an issue here in the lcsort gem or in the voyager data (or both).