[Feature]: optimize the ecma version check.

[easy1090]

What problem does this feature solve?

1. Support users in configuring the version number for ECMAScript testing.
2. Support for ecma version 8.

What does the proposed API look like?

linter: {
        rules: {
          'ecma-version-check': [
            'Error',
            {
              checkVersion: 7, // enum, 6 | 7 | 8
              exclude: [] // exclude some files. 
            },
          ],
        },
    }