updates in version 1beta:
1. significantly reduce NCBI server queries in both slow and fast mode
2. correct the bug about identical sequence of differnet gi numbers

updates in version 1.2:
1. automatic update local database for fast mode every 4 months
2. notified the update date in the webpage.

future plans:
1. suggest options when your result is not satisifatory
2. more parameters in blast?