Upgrade dependencies and review installation warnings

[mattcolegate]

Logs from the latest Travis runs show a lot of packages are outdated:

$ npm install 

npm WARN deprecated request@2.88.2: request has been deprecated, see https://github.com/request/request/issues/3142

npm WARN deprecated loopback-boot@2.28.0: This version is no longer supported, please upgrade to 3.x

npm WARN deprecated loopback-component-explorer@4.3.1: This version is no longer supported, please upgrade to 6.x

npm WARN deprecated swagger-ui@2.2.10: No longer maintained, please upgrade to swagger-ui@3.

npm WARN deprecated json3@3.3.2: Please use the native JSON object instead of JSON 3

npm WARN deprecated request@2.79.0: request has been deprecated, see https://github.com/request/request/issues/3142

npm WARN deprecated hawk@3.1.3: This module moved to @hapi/hawk. Please make sure to switch over as this distribution is no longer supported and may contain bugs and critical security issues.

npm WARN deprecated cryptiles@2.0.5: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).

npm WARN deprecated hoek@2.16.3: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).

npm WARN deprecated sntp@1.0.9: This module moved to @hapi/sntp. Please make sure to switch over as this distribution is no longer supported and may contain bugs and critical security issues.

npm WARN deprecated boom@2.10.1: This version has been deprecated in accordance with the hapi support policy (hapi.im/support). Please upgrade to the latest version to get the best features, bug fixes, and security patches. If you are unable to upgrade at this time, paid support is available for older versions (hapi.im/commercial).

npm WARN deprecated core-js@2.6.11: core-js@<3 is no longer maintained and not recommended for usage due to the number of issues. Please, upgrade your dependencies to the actual version of core-js@3.

npm WARN deprecated resolve-url@0.2.1: https://github.com/lydell/resolve-url#deprecated

npm WARN deprecated urix@0.1.0: Please see https://github.com/lydell/urix#deprecated

These need to be brought up to date.