Update the-isme-journal.csl: ISMEJ uses and="text" for author-short

The author guideline says to use the ampersand (http://mts-isme.nature.com/cgi-bin/main.plex?form_type=display_auth_instructions), but actually published papers use the text "and".
Merge pull request #1270 from and3k/patch-1

Update the-isme-journal.csl: ISMEJ uses and="text" for author-short