Add terraform and manual installation support (#4246)

This tweaks the BYOC cloud installation methods to enable manual
installation; and installation via terraform. Example commands:

To install automatically via CloudFormation: `earthly cloud install
--via cloudformation --name <stack-name>`

To install automatically via Terraform: `earthly cloud install --via
terraform`

To install manually:
```
earthly cloud install \
   --name <name> \
  --aws-account-id <aws-account-id> \
  --aws-region <aws-region> \
  --aws-security-group-id <aws-security-group-id> \
  --aws-ssh-key-id <aws-ssh-key-id> \
  --aws-subnet-id <aws-subnet-id> \
  --aws-instance-profile-arn <aws-instance-profile-arn> \
  --aws-earthly-access-role-arn <aws-earthly-access-role-arn>
```

Docs forthcoming on the new installation options.

---------

Co-authored-by: Brandon Schurman <brandon@earthly.dev>

CHANGELOG for v0.8.14

Signed-off-by: Alex Couture-Beil <alex@earthly.dev>

CHANGELOG for v0.8.13

CHANGELOG for v0.8.12

CHANGELOG for v0.8.11

CHANGELOG for v0.8.10

CHANGELOG for v0.8.9 (#4058)

CHANGELOG for v0.8.8

CHANGELOG for v0.8.7

update changelog and documentation for v0.8.6 (#3920)

Update changelog and docs for v0.8.6