find plugins in the current directory without having to specify `./`

[finishes #82776732]
Add `--guid` flag to `cf app`

- Allow users to get the guid of an application with a guid flag

[finishes #76459212]

Signed-off-by: George Price <gwprice@mac.com>
`-h` and `--h` should not report as invalid flags

[#69038672]
Add command help text to `cf plugins`

[#82777012]

Signed-off-by: George Price <gwprice@mac.com>
Update README.md
Update help text for `cf update-buildpack` and `cf create-buildpack`

[#82828946]

Signed-off-by: Simon Leung <leungs@us.ibm.com>
Fix invalid usage of create-space

Before Fix: If cf user does
'cf create-space my-space blahablaha'
then its success

After Fix:If cf user does
'cf create-space my-space blahablaha'
then it will fail with proper reason
Fix the args validation in below commands
'cf create-space SPACE blahblah'
'cf orgs blhablah'
'cf spaces blahblah'
'cf update-service SERVICE blahblah'
'cf marketplace  blahblah'
'cf delete-service SERVICE_INSTANCE  blahblah'
'cf services blahblah'
'cf plugins blahblah'
'cf feature-flags blahblah'
'cf create-space my-space blahablaha'
'cf app APPNAME  blahablaha'
'cf delete APPNAME blahblah'
'cf service-access blahblah'
'cf service-auth-tokens blahblah'
'cf service-brokers blahblah'
'cf delete-orphaned-routes'
'cf apps blahblah'
'cf restart APP blahblah'
'cf buildpacks blahblah'
'cf running-environment-variable-group  blahblah'
'cf staging-environment-variable-group  blahblah'
'cf space-quotas blahblah'
'cf quotas  blahblah'
'cf routes blahblah'
'cf start APP blahblah'

for example
Before Fix: If cf user does
'cf orgs  blahblah'
the command is success but ignord the second argument

After Fix:If cf user does
'cf orgs  blahblah'
the command will with proper reason