chore: 0.11.0 release

oddly 0.10.0 release has been published in the past already.. it's unclear why...

This is what I found:

$ yarn info angular-in-memory-web-api
...
...
    '0.7.0': '2018-11-01T07:41:14.441Z',
    '0.8.0': '2018-12-21T20:45:08.558Z',
    '0.9.0': '2019-08-21T12:28:01.077Z',
    '0.10.0': '2020-03-13T00:40:14.345Z'
  },
...

chore: release 0.10.0

* Updates some types to account for the `ModuleWithProviders` breaking change.
* Updates to Gulp 4 in order to avoid issues with Node 12.

chore: release 0.8.0

upgrade to rxjs v6 (#185)

* ci: update the ci environment to nodejs v8
* feat: update to rxjs@6.0.0-beta.1
* build: version as 0.6.0

fix: simulated HTTP errors now delayed as expected (#182)

closes #180

also fixes type error (#180)