build: bump for 0.6.4.

Fix LICENSE issue with cmake

release: libbson-0.6.0!

build: reset bson interface age.

build: release libbson 0.4.0.

release libbson-1.0 version 0.2.4.

build: bump for 0.2.2 release.

build: bump version for release of 0.2.0.