Re-implemented history management.

To make refreshing of a page work, added .htaccess file that
directs all api-URL-s to index.html.

Currently using URL in form: some-path/api:Ext.ClassName
I would like to use: some-path/api/Ext.ClassName

But I didn't figure out how to make them work, especially so that
it could be used from a local filesystem.  When the basedir of
the app changes, you can't use relative URL-s any more.