www/py-bleach: Update to 1.4

- Update to 1.4
- Switch from GITHUB to CHEESESHOP for MASTER_SITES
- Add BUILD_DEPENDS on six
- Update minimum version for html5lib RUN_DEPENDS
- Add TESTS option and tweak existing QA/Test entries
- Modernize Python framework entries
- Add LICENSE_FILE

Changes:

  * https://github.com/jsocol/bleach/blob/v1.4/CHANGES

PR:		146461
Submitted by:	Muhammad Rahman <5u623l20 at gmail dotcom> (with changes)


git-svn-id: svn+ssh://svn.freebsd.org/ports/head@366588 35697150-7ecd-e111-bb59-0022644237b5