Allow adding custom aspects to multipart upload

[mmuller88]

• In conjunction with Allow adding custom aspects to multipart upload alfresco-remote-api#232
• 10 May Alfresco Hackathon. Add aspectnames parameter to POST multipart children endpoint. Add unit test (https://community.alfresco.com/docs/DOC-8142-global-virtual-hack-a-thon-spring-2019)
• https://api-explorer.alfresco.com/api-explorer/#!/nodes/createNode already allow to add custom aspects to the node you create. The same should be allowed with using multipart.

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[mmuller88]

As part of the 10 May Alfresco Hackathon