main: Stop importing patternfly.css

* Stop importing cockpit's base1/patternfly.css

This is deprecated API and will be dropped at some point, in favor
of projects shipping their own CSS.

Install and import the styles from PF4 now.

* Use webpack based string replacement for removing the font-face rules from PF4

Doing the seddery in Makefile breaks `npm run build`, webpack watching,
and is generally brittle.
Do the font replacement hacking with `string-replace-loader`, which fits into webpack much more nicely.

There is still some potential simplification by not duplicating the
entire scss loader chain.

Co-authored-by: Martin Pitt <martin@piware.de>

Closes #315

test/check-application

@@ -20,16 +20,16 @@ class TestApplication(testlib.MachineCase):
 
         self.login_and_go("/starter-kit")
         # verify expected heading
-        b.wait_text(".container-fluid h2", "Starter Kit")
+        b.wait_text("h2.pf-c-title", "Starter Kit")
 
         # verify expected host name
         hostname = m.execute("hostname").strip()
-        b.wait_text(".container-fluid p", "Running on " + hostname)
+        b.wait_in_text("h4.pf-c-alert__title", "Running on " + hostname)
 
         # change current hostname
         m.execute("echo new-%s > /etc/hostname" % hostname)
         # verify new hostname name
-        b.wait_text(".container-fluid p", "Running on new-" + hostname)
+        b.wait_in_text("h4.pf-c-alert__title", "Running on new-" + hostname)
 
         # change language to German
         b.switch_to_top()
@@ -48,7 +48,7 @@ class TestApplication(testlib.MachineCase):
         b.go("/starter-kit")
         b.enter_page("/starter-kit")
         # page label (from js) should be translated
-        b.wait_in_text(".container-fluid p", "Läuft auf")
+        b.wait_in_text("h4.pf-c-alert__title", "Läuft auf")
 
 if __name__ == '__main__':
     testlib.test_main()