PostgreSQL 10 reports its version as only `major.minor`, so it can’t be parsed with semver. The `server_version_num` setting is a major version followed by a four-digit minor version since version 10, and was a three-digit major version followed by a two-digit minor version before that.
* Work on converting lib to standard
* Finish updating lib
* Finish linting lib
* Format test files
* Add .eslintrc with standard format
* Supply full path to eslint bin
* Move lint command to package.json
* Add eslint as dev dependency
A long standing bug was the pure JS client didn't accept or call a callback on `client.end`. This is inconsistent with both the documentation & general node patterns.
This fixes the issue & adds a test. The issue did not exist in the native version of the client.
