Adds link method for adding hyperlinks

Fixes: tartley#134

.gitignore

@@ -5,6 +5,7 @@ dist
 tags
 virtualenv
 build
+.tox
 
 # PyCharm
-.idea
+.idea

README.rst

@@ -146,6 +146,18 @@ Available formatting constants are::
 ``Style.RESET_ALL`` resets foreground, background, and brightness. Colorama will
 perform this reset automatically on program exit.
 
+Links
+-----
+
+Links are a new (2017) ANSI extension that mimics the HTML <a> blocks. You should
+be using it with care as many terminals are not supporting it yet.
+
+.. code-block:: python
+
+    from colorama import init, link
+
+    init()
+    print(link('http://example.com', 'click me'))
 
 Cursor Positioning
 ------------------

colorama/__init__.py

@@ -1,6 +1,6 @@
 # Copyright Jonathan Hartley 2013. BSD 3-Clause license, see LICENSE file.
 from .initialise import init, deinit, reinit, colorama_text
-from .ansi import Fore, Back, Style, Cursor
+from .ansi import Fore, Back, Style, Cursor, link
 from .ansitowin32 import AnsiToWin32
 
 __version__ = '0.3.9'

colorama/ansi.py

@@ -21,6 +21,8 @@ def clear_screen(mode=2):
 def clear_line(mode=2):
     return CSI + str(mode) + 'K'
 
+def link(url, text):
+    return OSC + '8;;' + url + '\a' + text + OSC + '8;;\a'
 
 class AnsiCodes(object):
     def __init__(self):

colorama/tests/ansi_test.py

@@ -2,15 +2,15 @@
 import sys
 from unittest import TestCase, main
 
-from ..ansi import Back, Fore, Style
+from ..ansi import Back, Fore, Style, link
 from ..ansitowin32 import AnsiToWin32
 
 stdout_orig = sys.stdout
 stderr_orig = sys.stderr
 
 
 class AnsiTest(TestCase):
-    
+
     def setUp(self):
         # sanity check: stdout should be a file or StringIO object.
         # It will only be AnsiToWin32 if init() has previously wrapped it
@@ -71,6 +71,9 @@ def testStyleAttributes(self):
         self.assertEqual(Style.NORMAL, '\033[22m')
         self.assertEqual(Style.BRIGHT, '\033[1m')
 
+    def testLink(self):
+        output = link('http://example.com','This is a link')
+        self.assertEqual(output, '\033]8;;http://example.com\aThis is a link\033]8;;\a')
 
 if __name__ == '__main__':
     main()

demos/demo09-hyperlinks.py

@@ -0,0 +1,16 @@
+from __future__ import print_function
+import fixpath
+from colorama import colorama_text, Fore, link
+
+
+def main():
+    """automatically reset stdout"""
+    with colorama_text():
+        print(Fore.GREEN + 'text is green')
+        print(Fore.RESET + 'text is back to normal')
+        print('This ' + link('https://google.com', 'link') + ' should be clickable')
+
+    print('text is back to stdout')
+
+if __name__ == '__main__':
+    main()