hybrid-lambda v0.3-beta

Migrated from google-code.

Fixed a bug in hybrid-lambda-beta.tar.gz-0.2 version. When lambda coalescent was used, the parameters were computed wrong.

Compare to version hybrid-lambda-beta.tar.gz and hybrid-lambda-beta-0,1.tar.gz

1. Fixed bug for genealogy branch length (when simulating from a network).
2. Using boost functions for calculating the binomial coefficient. It can handle sample sizes up to 10^3 for Lambda coalescent. (NOTE: a bug was introduced in this step in the first attempt.)
3. Disabled log function by default. Use option '-log [FILE]' to enable.
4. Added new function to calculate the TMRCA for the gene trees.