Tests don't take ignored-docs into consideration, and have misleading comments

[chalin]

This is related to:

• 227

Consider the following tests: https://github.com/wjdp/htmltest/blob/19cc89c592316dc933a5b9dcadc0c9b771a5f0f0/htmldoc/document_store_test.go#L9-L30

Note, in particular, the following two situations where the comments and code don't match:

• https://github.com/wjdp/htmltest/blob/19cc89c592316dc933a5b9dcadc0c9b771a5f0f0/htmldoc/document_store_test.go#L16-L17
• https://github.com/wjdp/htmltest/blob/19cc89c592316dc933a5b9dcadc0c9b771a5f0f0/htmldoc/document_store_test.go#L28-L29

The issue runs a deeper that just incorrect comments because the notion of document count has changed since the following fix has landed:

• 181

/assign @chalin