refactor: Mask parser improvements (#1734)

* Reduced intermediate collections and allocations
while parsing and replacing parts of the mask
* Cleaned up some logic around applying/replacing
parts of the mask.
* Dropped some obsolete internal methods.
* Better API documentation.

Author: rkaraivanov

src/components/mask-input/mask-parser.spec.ts

@@ -151,7 +151,7 @@ describe('Mask parser', () => {
     const value = 'ak47';
     parser.mask = '####';
     const result = parser.replace(parser.apply(), value, 0, value.length);
-    expect(result.value).to.equal('____');
+    expect(result.value).to.equal('47__');
   });
 
   it('replace (invalid end)', () => {