version 130517 of Kaviar2, improved allele frequency computation

[Gustavo Glusman]

There is an updated version of Kaviar2 (130517), using the same data freeze as the previous version (120807) but with a significantly improved allele frequency computation method.

The new method makes better use of data from the large population sampling projects (1000 Genomes, ESP6500), in particular when computing the frequency of rare variants.

Feedback and bug reports are most welcome.

-- Gustavo