Add plugin types (#1527)

Covered following plugins
- addAttributesToSVGElement.js 
- addClassesToSVGElement.js 
- cleanupAttrs.js 
- convertEllipseToCircle.js 
- removeAttributesBySelector.js 
- removeAttrs.js 
- removeComments.js 
- removeDesc.js 
- removeDoctype.js 
- removeElementsByAttr.js 
- removeEmptyText.js 
- removeMetadata.js 
- removeRasterImages.js 
- removeScriptElement.js 
- removeStyleElement.js 
- removeTitle.js 
- removeXMLProcInst.js

plugins/cleanupAttrs.js

@@ -14,6 +14,12 @@ const regSpaces = /\s{2,}/g;
  * Cleanup attributes values from newlines, trailing and repeating spaces.
  *
  * @author Kir Belevich
+ *
+ * @type {import('../lib/types').Plugin<{
+ *   newlines?: boolean,
+ *   trim?: boolean,
+ *   spaces?: boolean
+ * }>}
  */
 exports.fn = (root, params) => {
   const { newlines = true, trim = true, spaces = true } = params;