(fix) works now with servers without mod_headers
fixes an error on apaches without mod_headers
version bump to 2.0.17
settings.php: read plugin version dynamically
higher specificity for medialement container styles
bump version to 2.0.18

* change license-header
* change readmes
* remove trailing whitespace in readmes
whitespace fix in readme.md
version bump
package.json added
Merge branch '2.0.x'

Conflicts:
	podlove-web-player/header.txt
	podlove-web-player/podlove-web-player.php
	podlove-web-player/readme.md
	podlove-web-player/readme.txt
	podlove-web-player/settings.php
	podlove-web-player/static/podlove-web-player.css
	podlove-web-player/static/podlove-web-player.js