add CHANGELOG.

bump version to 0.3.0

Strip leading and trailing whitespace from header field names by default. Fixes #1.

Add tox to test from 3.10 to 3.12. Bump required version back to 3.10. Add repository URL. Ignore dist.

update README

add LICENSE

test worksheet with merged cells. larger range

fix typo in README

Initial reader implementation. Tests for skipping blank rows.