Make pager start counting from 1, not 0

Problem/Motivation

The pager starts counting from 0, which for a human is very confusing as no page 0 exists. This also causes the page numbers displayed in the pager and in the URL to be different from each other.

Now when Views is looking to get into D8, then #1024226: Option to start Pager count at 1 instead of 0 → is related to this as well. Unless they will merge into one pager.

Beta phase evaluation

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Proposed resolution

Do not alter the internal page number, but only show a pager starting at 1 in the URL.

Remaining tasks

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User interface changes

None

API changes

None