Add field property to sequelizeConnection return value

[jedwards1211]

Now instead of wasting keystrokes with

    tasks: {
      type: userTaskConnection.connectionType,
      args: userTaskConnection.connectionArgs,
      resolve: userTaskConnection.resolve
    }

You can just write

  tasks: userTaskConnection.field

This PR leaves the connectionType and connectionArgs properties in place, and has no breaking changes.

[codecov-io]

Codecov Report

Merging #577 into master will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #577   +/-   ##
=======================================
  Coverage   94.98%   94.98%           
=======================================
  Files          11       11           
  Lines         379      379           
=======================================
  Hits          360      360           
  Misses         19       19

Impacted Files	Coverage Δ
src/relay.js	97.05% <ø> (ø)	:arrow_up:

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[jedwards1211]

I think the timeouts in the CI tests are too low?

[jedwards1211]

@mickhansen does it look good now?