Enable multiple serialisation strategies

[vmasek]

Support multiple array (object?) serialization strategies for the (query) parameters and headers

• [ ] create a wrapper function that will handle the serialisation based on the supported collectionFormat formats
  • Possible values are:
    • csv - (default) comma separated values foo,bar.
    • ssv - space-separated values foo bar.
    • tsv - tab separated values foo\tbar.
    • pipes - pipe separated values foo|bar.
    • multi - multiple parameter instances instead of multiple values for a single instance foo=bar&foo=baz. This is valid only for parameters in "query" or "formData".
• [ ] configuration or function itself should be providable/configurable via DI
• [ ] research what is the preferred/best way to serialize objects
  • JSON.stringyfy might be needed for the objects

A related issue with angular API client itself https://github.com/angular/angular/issues/19071