Update LastLoginTimestamp when importing for a new user

[phil-davis]

Description

Set the LastLoginTimestamp when a user is created for an import.
That prevents later code from executing "first time login" actions for the user when they next log in.
The importer already does the needed stuff to set up the user's file system etc. We don't want later code to do "bonus" stuff, like copying in the skeleton.

A test scenario has been added to cover importing when a skeleton dir is defined on the system. While doing that, I also improved the test code - it was not actually deleting imported users at the end of the scenario, and the simpleExport/userfoo fixture was missing a shares.jsonl file, which was causing the import to report a problem (but the files were being imported, so the existing tests were passing)

Related Issue

Fixes #234

How Has This Been Tested?

Manually rerun the sequence in the issue and observe that the skeleton files have not been accidentally added to the user's files.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[dpapac]

LGTM, if this is all it takes to prevent running actions, which usually only would be run on the first login -> ...should fix #234 👍🏼

Will leave the approval of the PR to jvillafanez

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[jvillafanez]

This should be documented somewhere.

[phil-davis]

This should be documented somewhere.

See doc PR owncloud/docs-server#1052

[phil-davis]

@jnweiger if you have a release branch in progress, then please cherry-pick (or however you want to do it) this into the release branch.

[jnweiger]

Thanks @phil-davis - merged into release-0.3.0