merged RC_1_2 into RC_2_0

add project-config.jam to the root directory

bump version to 2.0.4

clear seed flag when we receive an incomplete bitfield from a peer

add security audit documentation

use /etc/ssl/cert.pem to validate HTTPS trackers and web servers on M…

…acOS

Merge branch 'RC_1_2' into RC_2_0

update revision

fix contributing docs

bump version to 1.2.11