Merge 61997476-jdbc-service-detection to master

[Completes #61997476]
Update New Relic version

This change updates the limit of the New Relic version to 3.2.+.

[#62143886]
Merge 62143886-new-relic-update to master

[Completes #62143886]
Add FilteringPathname

This class behaves like Pathname but filters the filesystem and
is optionally immutable.

The implementation leans heavily on method_missing in order to
centralise the filtering, conversion, and mutability logic.

[#61738342]
Merge 61738342-application-droplet-abstractions to master

[#61738342]
First prototype of memory scaling

Drives the memory calculation in the droplet.

[#56495606]