CI Sparks - Some of them are available to install via CI Sparks, and I believe you can create sparks manually from existing git/bitbucket repos.
Composer - A lot of php frameworks such as Symphony are switching over to maintaining packages via Composer. It supports github/bitbucket and many more. Here's a guide to using Composer with CI.
Options 2 and 3 are preferable for maintainability.
We should move 3rd party libraries out of /application/libraries/ where we store LifePress specific libraries.
Options:
Options 2 and 3 are preferable for maintainability.