Fix nasty random crasher (early returns can be evil).   Make sure the number of tokens is set to zero when  returning an empty stringlist, since the caller iterates based on that value.  This crash was very sensitive to surrounding items in the BibTeX file.
Fix nasty random crasher (early returns can be evil).  
Make sure the number of tokens is set to zero when 
returning an empty stringlist, since the caller iterates
based on that value.  This crash was very
sensitive to surrounding items in the BibTeX file.


JackieXie168/skim,JackieXie168/skim,JackieXie168/skim,JackieXie168/skim,JackieXie168/skim