Enable support for modern SSL (#12524).

 * --ssl-protocol= option now accepts 'tlsv1.2', 'tlsv1.1', 'tlsv1.0'
   and 'default' as well as the existing 'tlsv1', 'sslv3', and 'any'.

 * The default is now none of the above, but rather QSsl::SecureProtocols,
   which means "whatever subset of ANY is still considered secure and also
   supported by the OpenSSL library in use".  (As of this writing, Qt's idea
   of "still considered secure" includes everything from SSLv3 on up, which
   is technically wrong -- SSLv3 has known breaks -- but we can live with.
   Qt currently doesn't have a way to select "TLSv1.0 and up".)
Make ciphersuite selection configurable; match Chromium by default. (#12524)

New option --ssl-ciphers takes a colon-separated list of OpenSSL
cipher names and sets the client cipher list to exactly that list.

The default for this option is arranged to match Chromium 35, which
has had its cipher selection optimized for the modern Web
(see https://briansmith.org/browser-ciphersuites-01.html for
rationales).  (Newer versions are the same except that they also add
ChaCha20-based ciphersuites, which OpenSSL 1.0.1 hasn't yet picked up.)
Remove the deprecated phantom.args.

The use of phantom.args has been deprecated (see commit 545a3f7)
since a long time ago (version 1.5, March 2012). Any old scripts
need to switch to use System#args instead.

https://github.com/ariya/phantomjs/issues/12527
Remove the deprecated phantom.scriptName.

The use of phantom.scriptName has been deprecated since System#args was
introduce (version 1.5, March 2012). Any old scripts need to migrate to
System#args.

https://github.com/ariya/phantomjs/issues/12529
Encode URLs when passing to JS: issues #12216 and #11035.

 * Use QUrl::toEncoded() instead of QUrl::toString() to compute
   WebPage.url, WebPage.frameUrl, the first argument to an
   onNavigationRequested hook, and the 'url' property of the object
   passed to an onResourceError hook.  This makes them consistent with
   the data passed to the onResourceRequested, onResourceReceived,
   and onResourceTimeout hooks, and with the semantics of WebPage.open(),
   WebPage.openUrl(), and the cookie jar.  (Issue #12216.)

 * Use m_currentFrame->baseUrl() instead of m_currentFrame->url() for
   WebPage.frameUrl; this is a partial workaround for a bug in QtWebKit
   which is the root cause of issue #11035.  Noticed while attempting to
   test the above changes.

 * Take care not to mangle the encoding of the url passed to the
   WebServer.listen callback function.  Necessary in order to test the
   above changes: not only should JS receive %-encoded URLs, the server's
   encoding of non-ASCII characters in URLs should be preserved; to test
   this thoroughly, a heinously non-Unicode-compatible encoding (Shift_JIS)
   is deliberately used for the URLs in all the new tests.
Add phantom.resolveRelativeUrl and phantom.fullyDecodeUrl.

These utility functions make it easier to work with encoded URLs.
See issues #12216 and #11035.