Changes to HtmlArea3 for Zope

• a htmlArea_demo method was added which allows to tinker with most of the features (just call it through the web, e.g. from the README tab)
• change to the Javascript code: the formatblock option Normal was renamed to Paragraph, since it yields a paragraph (p) tag; a new empty option Normal was added to the top of the list (this seems to work with Mozilla only).
• added a removeformats button (lacking an appropriate icon)
• when the bold button was the first in the line, a space was inserted behind it (fixed)
• the public version of HtmlArea for Zope (if more than one of the products is installed) can be selected via the environment variable HTMLAREA4ZOPE_PUBLIC
• changed the license to GPL

• some code cleanup

several improvements:

• the mixin class is not needed anymore (it is still there, of course); the methods can be used without mixing them in.
• new htmlArea() function which consistently takes care of both the textarea tag and the editor
• new named toolbar common suitable for pretty CI/CD-conforming pages; this is now the default
• auto-select of language support (browser button tooltips), according to browser setting and installed language files

Note:

Zope 2.6.1 might not be able anymore to refresh the product properly, possibly caused by the methods trick for public availability of the methods. Thus, refresh.txt was removed.