[Get.pm] Handle articles attributed to multiple months.
[Get.pm] Handle redundant EBSCO records a bit better.

I was annoyed by records without full text getting chosen over records with full text. This change might also help with title capitalization, though.
[Get.pm] Tweaks for sever-side changes.

The procedure for querying EBSCO is a bit cleaner now. (I finally figured out which fields are necessary.)
[Get.pm] Name the cache "cache.json".