Mongodb: 2.7.7

The level of patching here is getting a little silly. Mongo are
currently shifting around a fair bit of their codebase, and that is
currently causing the HEAD build to fail.

The devel build also needs patching, discussed
[here](https://jira.mongodb.org/browse/SERVER-15555), but that fix has
been merged into the HEAD and consequently is scoped to only the devel
build.

The last patch is the SConstruct file to accept 10.10 as a valid build
option on Yosemite, which is in neither stable, devel or HEAD currently.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Mongodb 2.6.5 & 2.7.7

Closes #32886.
Closes #33026.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
mongodb: update 2.6.5 bottle.