INSTALL specifies wrong minimum Python version

[Samuel Bronson]

In lp:bzr/2.4 and later, INSTALL says that bzr requires Python2.4 and cElementTree, when in fact these versions of bzr require at least Python 2.6 (which bundles cElementTree).

[Samuel Bronson (naesten)]

There are other files that do this, too, such as doc/en/admin-guide/introduction.txt; take a look at the results of this highly scientific grep:

bzr ls -RV0 | xargs -0 grep -nH -e 'python.*2\.[0-5]' -i
INSTALL:7:bzr requires Python2.4 and cElementTree:
bzrlib/__init__.py:52:# Python version 2.0 is (2, 0, 0, 'final', 0)." Additionally we use a
bzrlib/_btree_serializer_pyx.pyx:20:#python2.4 support
bzrlib/_chk_map_pyx.pyx:18:#python2.4 support
bzrlib/_chunks_to_lines_pyx.pyx:20:#python2.4 support
bzrlib/_dirstate_helpers_pyx.pyx:43:#python2.4 support, and other platform-dependent includes
bzrlib/_dirstate_helpers_pyx.pyx:1616: # on win32, python2.4 has e.errno == ERROR_DIRECTORY, but
bzrlib/_dirstate_helpers_pyx.pyx:1617: # python 2.5 has e.errno == EINVAL,
bzrlib/_export_c_api.h:48: /* (char *) is because python2.4 declares this api as 'char *' rather than
bzrlib/_groupcompress_pyx.pyx:19:#python2.4 support
bzrlib/_import_c_api.h:50: /* (char *) because Python2.4 defines this as (char *) rather than
bzrlib/_patiencediff_py.py:233: # jam 20060525 This is the python 2.4.1 difflib get_matching_blocks
bzrlib/_readdir_pyx.pyx:23:#python2.4 support
bzrlib/_rio_pyx.pyx:19:#python2.4 support
bzrlib/_walkdirs_win32.pyx:88: # We can't just declare this as 'readonly' because python2.4 doesn't define
bzrlib/cethread.py:44: # compatibility thunk for python-2.4 and python-2.5...
bzrlib/cleanup.py:163: # As correct as Python 2.4 allows.
bzrlib/commands.py:841: # for python 2.5 and later, optparse raises this exception if a non-ascii
bzrlib/diff.py:88: # Special workaround for Python2.3, where difflib fails if
bzrlib/dirstate.py:3943: # on win32, python2.4 has e.errno == ERROR_DIRECTORY, but
bzrlib/dirstate.py:3944: # python 2.5 has e.errno == EINVAL,
bzrlib/errors.py:181: # exceptions are old-style classes in python2.4 (but new in 2.5).
bzrlib/errors.py:721: # Python 2.4 have to be old-style classes so properties don't work.
bzrlib/errors.py:3069: # nb: in python2.4 socket.error doesn't have a useful repr
bzrlib/fifo_cache.py:43: # Python2.5's has deque.remove, but Python2.4 does not
bzrlib/intset.py:194: File "/usr/lib/python2.4/doctest.py", line 1243, in __run
bzrlib/library_state.py:53: BzrLibraryState implements the Python 2.5 Context Manager protocol
bzrlib/osutils.py:289:# In Python 2.4.2 and older, os.path.abspath and os.path.realpath
bzrlib/osutils.py:915: # Python 2.4 and later have os.urandom,
bzrlib/osutils.py:1181: os.path.commonprefix (python2.4) has a bad bug that it works just
bzrlib/osutils.py:1642: 2) Windows, Python2.4, uses errno == ERROR_DIRECTORY (267)
bzrlib/osutils.py:1644: 3) Windows, Python2.5 uses errno == EINVAL and
bzrlib/plugins/launchpad/lp_registration.py:57: # In python2.4 xmlrpclib.Transport is a old-style class, and does not
bzrlib/plugins/launchpad/test_register.py:102: # Python 2.5's xmlrpclib looks for this.
bzrlib/pyutils.py:71:# +SKIP is not recognized by python2.4
bzrlib/remote.py:3250: A replacement for extractall, which is not presen...