Stuck on bench init frappe-bench

I am stuck on this step of the installation guide, would appreciate any help.

$ bench init frappe-bench
Already using interpreter /usr/bin/python2.7 app frappe
Cloning into ‘frappe’… frappe
cookie@0.3.1 node_modules/cookie

redis@2.6.3 node_modules/redis
├── double-ended-queue@2.1.0-0
├── redis-commands@1.3.0
└── redis-parser@2.3.0

superagent@3.3.1 node_modules/superagent
├── methods@1.1.2
├── component-emitter@1.2.1
├── cookiejar@2.1.0
├── extend@3.0.0
├── mime@1.3.4
├── formidable@1.0.17
├── qs@6.3.0
├── debug@2.6.0 (ms@0.7.2)
├── readable-stream@2.2.2 (buffer-shims@1.0.0, string_decoder@0.10.31, inherits@2.0.3, process-nextick-args@1.0.7, util-deprecate@1.0.2, core-util-is@1.0.2, isarray@1.0.0)
└── form-data@2.1.2 (asynckit@0.4.0, combined-stream@1.0.5, mime-types@2.1.13)

express@4.14.0 node_modules/express
├── escape-html@1.0.3
├── array-flatten@1.1.1
├── cookie-signature@1.0.6
├── utils-merge@1.0.0
├── content-type@1.0.2
├── merge-descriptors@1.0.1
├── encodeurl@1.0.1
├── methods@1.1.2
├── etag@1.7.0
├── content-disposition@0.5.1
├── range-parser@1.2.0
├── fresh@0.3.0
├── vary@1.1.0
├── parseurl@1.3.1
├── path-to-regexp@0.1.7
├── serve-static@1.11.1
├── depd@1.1.0
├── qs@6.2.0
├── on-finished@2.3.0 (ee-first@1.1.1)
├── finalhandler@0.5.0 (unpipe@1.0.0, statuses@1.3.1)
├── debug@2.2.0 (ms@0.7.1)
├── proxy-addr@1.1.2 (forwarded@0.1.0, ipaddr.js@1.1.1)
├── send@0.14.1 (destroy@1.0.4, ms@0.7.1, statuses@1.3.1, mime@1.3.4, http-errors@1.5.1)
├── type-is@1.6.14 (media-typer@0.3.0, mime-types@2.1.13)
└── accepts@1.3.3 (negotiator@0.6.1, mime-types@2.1.13) node_modules/
├── object-assign@4.1.0
├── has-binary@0.1.7 (isarray@0.0.1)
├── debug@2.3.3 (ms@0.7.2)
├── (isarray@0.0.1, json3@3.3.2, component-emitter@1.1.2, debug@2.2.0)
├── (base64id@1.0.0,, ws@1.1.1, accepts@1.3.3)
└── (to-array@0.1.4, component-emitter@1.2.1, indexof@0.0.1, component-bind@1.0.0, backo2@1.0.2, object-component@0.0.3, parseuri@0.0.5,
Wrote ./assets/js/print_format_v3.min.js - 18k
Wrote ./assets/js/frappe-web.min.js - 132k
Wrote ./assets/js/form.min.js - 141k
Wrote ./assets/js/report.min.js - 162k
Wrote ./assets/css/list.min.css - 9k
Wrote ./assets/js/d3.min.js - 343k
Wrote ./assets/css/report.min.css - 8k
Wrote ./assets/css/frappe-web.css - 64k
Wrote ./assets/js/list.min.js - 95k
Wrote ./assets/js/dialog.min.js - 63k
Wrote ./assets/js/desk.min.js - 251k
Wrote ./assets/css/form.min.css - 4k
Wrote ./assets/js/editor.min.js - 27k
Wrote ./assets/js/libs.min.js - 687k
Wrote ./assets/css/desk.min.css - 256k
Wrote ./assets/css/frappe-rtl.css - 31k
Wrote ./assets/css/module.min.css - 2k
INFO:bench.utils:setting up backups
installing frappe
Traceback (most recent call last):
  File "/usr/bin/bench", line 9, in <module>
    load_entry_point('bench', 'console_scripts', 'bench')()
  File "/home/al/programs/bench-repo/bench/", line 40, in cli
  File "/usr/lib64/python2.7/site-packages/click/", line 716, in __call__
    return self.main(*args, **kwargs)
  File "/usr/lib64/python2.7/site-packages/click/", line 696, in main
    rv = self.invoke(ctx)
  File "/usr/lib64/python2.7/site-packages/click/", line 1060, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/lib64/python2.7/site-packages/click/", line 889, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/lib64/python2.7/site-packages/click/", line 534, in invoke
    return callback(*args, **kwargs)
  File "/home/al/programs/bench-repo/bench/commands/", line 19, in init
    verbose=verbose, clone_from=clone_from)
  File "/home/al/programs/bench-repo/bench/", line 73, in init
  File "/home/al/programs/bench-repo/bench/", line 202, in setup_backups
    logfile=os.path.join(get_bench_dir(bench_path=bench_path), 'logs', 'backup.log')))
  File "/home/al/programs/bench-repo/bench/", line 205, in add_to_crontab
    current_crontab = read_crontab()
  File "/home/al/programs/bench-repo/bench/", line 216, in read_crontab
    s = subprocess.Popen(["crontab", "-l"], stdin=subprocess.PIPE, stdout=subprocess.PIPE)
  File "/usr/lib64/python2.7/", line 711, in __init__
    errread, errwrite)
  File "/usr/lib64/python2.7/", line 1343, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory

I fixed it by installing cron (crontab) in my package manager.
Should cron be listed as pre-requisite?

Sure! Can you fix the readme and send a pull request?