added and index page for series

[frederikhogenbosch98]

added support for an overview page of all series

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[asmecher]

Thanks, @frederikhogenbosch98! Before I review/merge this, could you create an issue describing this change and referring to this pull request over at https://github.com/pkp/pkp-lib/issues/?

[frederikhogenbosch98]

The issue was actually created some time ago, but I believe the pull request was never made.

pkp-lib/issues/6086

[asmecher]

There's another pull request here: https://github.com/pkp/omp/pull/855

Yours seems to be based on that; are you working with that developer, or is this dusting off/updating someone else's work?

[frederikhogenbosch98]

I am indeed working with that developer. Is there a reason why the previous pull request was never merged?