Sanic CLI upgrade

[ahopkins]

Fairly simple changes here:

1. Add support for path.to.server:app as well as existing path.to.server.app
2. Add a -v/--version to display Sanic version info
3. Add some more help_text
4. Add --access-logs/--no-access-logs

$ sanic -h
usage: sanic [-h] [-H HOST] [-p PORT] [-u UNIX] [--cert CERT] [--key KEY]
             [-w WORKERS] [--debug] [--access-logs | --no-access-logs] [-v]
             module

                 Sanic
         Build Fast. Run Fast.

positional arguments:
  module                path to your Sanic app. Example: path.to.server:app

optional arguments:
  -h, --help            show this help message and exit
  -H HOST, --host HOST  host address [default 127.0.0.1]
  -p PORT, --port PORT  port to serve on [default 8000]
  -u UNIX, --unix UNIX  location of unix socket
  --cert CERT           location of certificate for SSL
  --key KEY             location of keyfile for SSL.
  -w WORKERS, --workers WORKERS
                        number of worker processes [default 1]
  --debug
  --access-logs         display access logs
  --no-access-logs      no display access logs
  -v, --version         show program's version number and exit

[codecov]

Codecov Report

Merging #1962 into master will decrease coverage by 0.03%.
The diff coverage is 90.90%.

@@            Coverage Diff             @@
##           master    #1962      +/-   ##
==========================================
- Coverage   92.38%   92.34%   -0.04%     
==========================================
  Files          29       29              
  Lines        3242     3254      +12     
  Branches      571      572       +1     
==========================================
+ Hits         2995     3005      +10     
- Misses        169      170       +1     
- Partials       78       79       +1     

Impacted Files	Coverage Δ
sanic/__main__.py	78.84% <90.90%> (+1.34%)	⬆️

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[ashleysommer]

Looks great! Thanks!