Clarify `ignoreBlank` with `presence` validator

[Sumeet Attree]

Environment

• Ember Version: 3.6.0
• Ember CLI Version: 3.6.0
• Ember CP Validations Version: 4.0.0-beta.5

I would have expected ignoreBlank: true to consider '' as a valid value. But apparently it isn't. What was the original intention behind ignoreBlank? I was expecting something like rails, where ignoreBlank (allowBlank: true) to actually consider '' value as a valid value.

Edit:

  //  Shouldn't this line: 
  let _isPresent = ignoreBlank ? isPresent(v) : !isEmpty(v);

  // be this short circuit instead?
  if (ignoreBlank === true && v == '') {
    return true;
  }

[Kevin C]

I think the naming is confusing. I think what it means is that all the following will be considered invalid:

• ''
• ' '

I think it is intended to essentially treat whitespace/empty string as empty/invalid.