switch word_delimeter based filter

[pschoffer]

Description of the Change

word_delimiter_graph is recommended in ElasticSearch 7.x over word_delimiter filter currently used by ewp_word_delimiter.

This change switches the underlying filter to match the recommendation.

Alternate Designs

Benefits

Possible Drawbacks

Verification Process

Run index --setup, verify the filter still splits correct on caseChange and non-alpha symbols.

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests passed.

Applicable Issues

Changelog Entry

Changed: The base filter for ewp_word_delimiter was changed from word_delimiter to word_delimiter_graph based on ElasticSearch recommendation.

[jesse-greathouse]

Nice suggestion from @yolih