Use smaller dataset with prices

[renekrie]

• Use smaller product dataset with prices for all products (ca. 20k) in quickstart.sh.
• Remove price filter appended in solrconfig.xml
• Change README to use smaller dataset. Large dataset still available for download and to be mentioned in README

[renekrie]

Dataset available at: https://querqy.org/datasets/icecat/icecat-products-w_price-19k-20201127.tar.gz

[renekrie]

The dataset is now available at: https://querqy.org/datasets/icecat/icecat-products-w_price-19k-20201127.tgz. This archive contains multiple files. We will need icecat-products-w_price-19k-20201127.json for indexing.

[atarora]

@renekrie is this still a valid issue?