WebSearch: distribute all keywords for grouped terms

• Change behavior for SPIRES syntax parser so that keywords are assumed to extend to the next conjunction or the end of line, e.g.: find journal aa bb cc and kw dd becomes: journal:aa and journal:bb and journal:cc and keyword:dd
  
  This was the behavior before with title:, keyword: and fulltext: queries; this patch extends this behavior to all keywords.
  
  (addresses #113)

• Special-case space removal for journals: journal references of the form: find j jhep, 0903, 024 become: journal:jhep,0903,024