[Bug] sanitizerConfig works incorrectly

[gohabereg]

Description

BlockTool.sanitize property returns an object with the same shape as Tool's data object. sanitize object container SanitizerConfig as leafs.

Examples:

{
  text: {
   br: true,
  },
}

{
  caption: {
    text: { br: true }
  }
}

Internal BlockTool class has baseSanitizeConfig and sanitizeConfig preoptries.

baseSanitizerConfig is merge of sanitize configs of inline tools and tunes used by Block tool

sanitizeConfig returns an object with the shape of original tool.sanitize, but each with merged baseSanitizerConfig to each property.

Example
Tool config: { text: { br: true } }
Inline Tool config: { b: true }
Tune config: { sup: true }

baseSanitizeConfig would be { b: true, sup: true }
sanitizeConfig would be { text: { br: true, b: true, sup: true } }

Problems

1. baseSanitizeConfig should be renamed so its name reflects it is a merge of Tunes and Inline Tools sanitize configs
2. Return type of sanitizeConfig should be changed to reflect shape of the data object
3. sanitizeConfig should be able to process nested fields of data object (also need to check the same in Saver module)