[EXT-144] Fix url_type to allow dashes

backport url_type checking allowance from WP-VIP
[EXT-144] bad request instead of server error

change from 500 error to 400 error
Set the share message for links in the Engage widget js

Currently, the share widget doesn't include a message, so links shared
through Twitter only include the URL shared. It would be nice to have
the widget share message template filterable or set through an option,
but setting the share message to the post title seems like a sensible
default.
Merge pull request #9 from thanj/than/share-message

Set the share message for links in the Engage widget js
Merge pull request #5 from janrain/ext144

[EXT-144] Fix url_type to allow dashes
[EXT-143] rollback loadjs autoconfigure

because of cnames and custom load.js locations we cannot simplify this
feature.
Merge pull request #10 from janrain/ext143

[EXT-143] rollback loadjs autoconfigure
DEV: Fix Compatability
[EXT-144] lets not break everything ;)
[DEV] Updated versioning to 0.2.2
Escape strings passed to share widget properly

Calling `htmlspecialchars()` on this text more-or-less does the job of
preventing XSS attacks, but it makes the titles and descriptions that
are passed to the share widget have ugly entities like `&#8217;` instead
of single quotes.

`esc_js()` handles replacing invalid UTF8 or dangerous entities, as well as
adding slashes before single quotes. Also, `esc_url()` ensures that only
valid URLs are shared.
Call untrailingslashit on plugin dir path and plugin dir url

The functions `plugin_dir_path()` and `plugin_dir_url()` both add
their own trailing slashes. Currently the plugin builds a lot of links
with double slashes in them, like
`siteurl.com/wp-content/plugins/janrain-capture//stylesheet.css`
because its building links by adding another slash ast the end of the
output of these functions.

I don't know if this actually breaks in any common web servers, but it's
annoying and should probably be fixed.
[DEV] update default screens to work with new Plugins flow!
Make the $capture object a public global

Currently all global variables are completely encapsulated, so there's
no way for developers of other plugins to hook into any of this plugin's
actions and modify them.

This goes against the WordPress way of exposing filters so that plugins
can build on each other.

With this change, for example, it's possible for a theme to remove the
Capture scripts from views such as modal windows that don't need them,
by doing something (admittedly clumsy) like this:

    global $capture;
    $capture_ui =& $capture->ui;
    remove_action( 'wp_head', array( $capture_ui, 'head' ) );
    remove_action( 'wp_head', array( $capture_ui, 'sign_in_screen_js' ) );
    remove_action( 'wp_enqueue_scripts', array( $capture_ui, 'register_scripts' ) );
    remove_action( 'wp_footer', array( $capture_ui, 'share_js' ) );
    remove_action( 'wp_footer', array( $capture_ui, 'sign_in_screen' ) );
    wp_dequeue_style( 'janrain_share' );

With the current plugin, there's no way to do this at all, or to
override the settings passed to the widget.
Re-add the default styles

Where did these go?  here they are!
updated verify screens
updated signin screens
updated public profile screens
update forgot password screens
update edit profile screens