README problems

[rddunlap]

Issues with README.md:

a. duplicated words: "Replace with the with the actual locations"
b. "actual locations of compile_commands.json and fix_includes.py": AFAICT there is no fix_includes.py.
c. In "5. If there are still problems." change the ending '.' to a ':'.
d. Add a note: uses Python3, will fail if Python2 is used.
e. Add a note: copy all of IWYUScripts/* to the linux/ repository (or does just using an updated PATH work?)

In general, README.md is not friendly to new users. (Yes, I am trying to use it.)

My current problem is this (although it could easily be a user problem):

python3 ./single_iwyu.py -c X64/compile_commands.json -d -s fs/gfs2/super.c
Traceback (most recent call last):
File "/work/lnx/repo/lnx-gfs2/./single_iwyu.py", line 76, in
main(args.commands, args.fixer_path, args.filters, args.specific_command)
File "/work/lnx/repo/lnx-gfs2/./single_iwyu.py", line 26, in main
perform_iwyu(
File "/work/lnx/repo/lnx-gfs2/lib/utils.py", line 198, in perform_iwyu
if not run_cleaned_iwyu(iwyu_cmd, quote_cleaner, fix_includes, debug=debug):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/work/lnx/repo/lnx-gfs2/lib/utils.py", line 128, in run_cleaned_iwyu
_, err = subprocess.Popen(iwyu, stderr=subprocess.PIPE, text=True).communicate()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib64/python3.11/subprocess.py", line 1026, in init
self._execute_child(args, executable, preexec_fn, close_fds,
File "/usr/lib64/python3.11/subprocess.py", line 1953, in _execute_child
raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'include-what-you-use'