Hints kitten: Overhaul making it more intelligent

It now uses information about the geometry of the screen.
So URLs that stretch over multiple lines are detected even if there is a
hard line break in between (some programs like mutt generate these).

kitty_tests/hints.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
+
+
+from . import BaseTest
+
+
+class TestHints(BaseTest):
+
+    def test_url_hints(self):
+        from kittens.hints.main import parse_hints_args, functions_for, mark, convert_text
+        args = parse_hints_args([])[0]
+        pattern, post_processors = functions_for(args)
+
+        def create_marks(text, cols=20):
+            text = convert_text(text, cols)
+            return tuple(mark(pattern, post_processors, text, args))
+
+        def t(text, url, cols=20):
+            marks = create_marks(text, cols)
+            urls = [m.text for m in marks]
+            self.ae(urls, [url])
+
+        u = 'http://test.me/'
+        t(u, 'http://test.me/')
+        t('"{}"'.format(u), u)
+        t('({})'.format(u), u)
+        t(u + '\nxxx', u + 'xxx', len(u))
+        t('link:{}[xxx]'.format(u), u)