Support GroupTable component

[feathergrass]

• Expand / Collapse a node (selected by label).
• Get a collection of inner rows for further assertions.

Updates

New component GroupTable is introduced.

It supports the following two conditions:

• Conditions#EXPANDED - checks that all group rows are expanded
• Conditions#COLLAPSED - checks that all group rows are collapsed

The GroupTable component has the following method:

• expandAll() - expands all group rows
• collapseAll() - collapses all group rows
• expand(By groupRowSelector) - expands first met group row that matches passed selector
• collapse(By groupRowSelector) - collapses first met group row that matches passed selector

Usage example

@Test
void testExpandAll() {
    $c(AppMenu)
            .openItem(Menus.PRODUCT_BROWSE)

    $c(GroupTable, 'productsTable')
            .shouldBe(Condition.visible)
            .expandAll()
            .shouldBe(Conditions.EXPANDED)
}

@Test
void testCollapseAll() {
    $c(AppMenu)
            .openItem(Menus.PRODUCT_BROWSE)

    $c(GroupTable, 'productsTable')
            .shouldBe(Condition.visible)
            .collapseAll()
            .shouldBe(Conditions.COLLAPSED)
}

@Test
void testExpandSpecified() {
    $c(AppMenu)
            .openItem(Menus.PRODUCT_BROWSE)

    // only two groups exist
    $c(GroupTable, 'productsTable')
            .expand(withText('123'))
            .expand(withText('321'))
            .shouldBe(Conditions.EXPANDED)
}

[natfirst]

expandAll() method does not expand all groups, only the first one in the table

collapseAll() method does nothing

[natfirst]

The second part of the issue will be implemented in another issue #66

[natfirst]

Also, add an ability to expand only one selected group