python: bump to 2.7.6

Even though jumping from 2.7.3 to 2.7.6 looks like a minor version
bump, it is in fact a fairly significant one, because a good number of
changes to help cross-compilation have been merged into Python
upstream. Therefore, most of our patches are affected by this change.

In detail, this commit:

 * Renames all the patches to follow the naming convention of patches
   in Buildroot: the patch file names should not have any version
   number.

 * The patches numbered above 100, that add configuration options to
   disable certain modules of the Python standard library, are only
   renamed and slightly adapted, they didn't change that much.

 * The patches numbered below 100 are almost entirely rewritten: many
   of the cross-compilation problems that used to exist in Python
   2.7.3 no longer exist, and the number of remaining problems is
   smaller, and can be fixed with smaller patches.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python/python-009-no-termcap-host-path.patch

@@ -0,0 +1,23 @@
+Don't look in /usr/lib/termcap for libraries
+
+Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+
+
+Index: b/setup.py
+===================================================================
+--- a/setup.py
++++ b/setup.py
+@@ -760,12 +760,9 @@
+                 pass # Issue 7384: Already linked against curses or tinfo.
+             elif curses_library:
+                 readline_libs.append(curses_library)
+-            elif self.compiler.find_library_file(lib_dirs +
+-                                                     ['/usr/lib/termcap'],
+-                                                     'termcap'):
++            elif self.compiler.find_library_file(lib_dirs, 'termcap'):
+                 readline_libs.append('termcap')
+             exts.append( Extension('readline', ['readline.c'],
+-                                   library_dirs=['/usr/lib/termcap'],
+                                    extra_link_args=readline_extra_link_args,
+                                    libraries=readline_libs) )
+         else: