Added Locator Handler methods

1. Updated addHandler method.
2. Added removeHandler method.
3. Updated docs.

API actualization.

1. Renamed method asFrame() to contentFrame().
2. Added method owner().
3. Updated documentation.

New methods 'with' and 'addHandler'

1. Added method 'with' with can replace 'withMethods' and 'subElements' methods.
2. Added method 'addHandler' with allows to adLocatorHandler to current page from WebElement.

Fix for usePage method and goto fixture combinations.

1. Fixed issue when goto is called from usePage callback.
2. Added use page as fixture.
3. Updated readme file.

Fixed issue with expect types.

1. Fixed issue with expect in web element. (Now it returns correct type instead of any)
2. Improved documentation.
3. Marked static method useExpect as deprecated.

Reduced dependency size.

This is none functional release:

1. Reduced dependency size by replacing lodash on lodash.clonedeep

New usePage function.

1. Added usePage function with provides ability to use several contexts in one test simultaneously.
2. Added tests for new method.
3. Updated docs and added github pages

Added new tab switch method.

1. Added new tab switch method, test and docs.

New use expect method.

1. New use expect method.
2. New integration test.
3. Updated pw-core version
4. Updated Readme

v.1.9.4

1. Fixed issue with .has(WebElement) method.