Merge branch 'release/2.4.12' into develop
Set default Riak version to v.1.4.9.
Merge branch 'feature/hc/riak149' into develop
Relax sysctl version constraint to < 0.5.0.

v0.5.0 contains breaking changes, see:
https://github.com/onehealth-cookbooks/sysctl/blob/master/CHANGELOG.md
Increase pessimistic version constraint on build-essential.
Merge branch 'halcyonCorsair-relax_sysctl_constraint' into develop
v2.4.13
Merge branch 'release/2.4.13'