[Release] C/C++ driver v2.7.0

[Michael Penick]

Hi,

We just released v2.7.0 of the C/C++ driver. This release includes initial support for protocol v5 as well as fixes for the duration type and token aware routing.

[CPP-464] Adding a node breaks token map reconstruction (and can cause long delays) (Bug)
[CPP-460] Heavy load when updating token maps on node addition (Bug)
[CPP-454] Duration type needs to use `int64_t` for the nanos component (Bug)
[CPP-443] Support for protocol DSEv1 and v5 (New Feature)

If your application is using v2.6.0 with the duration type it is highly recommended that your application upgrade to v2.7.0. The `nanos` component of duration now uses the `int64_t` type instead of `int32_t` which is needed to represent the full range of the `nanos` component.

Mike