appbuilder: suporte a button em AbstractPageBuilder.

Signed-off-by: Francisco Prates <mad.kanie@gmail.com>
shell: chama get_view_data() conservando a visao atual.

Signed-off-by: Francisco Prates <mad.kanie@gmail.com>
appbuilder: sincroniza itens de table e objetos se houver diferença
de quantidade.

Signed-off-by: Francisco Prates <mad.kanie@gmail.com>
appbuilder: permite atualizar ViewInput sem atualizar ViewSpec e ViewConfig.

Signed-off-by: Francisco Prates <mad.kanie@gmail.com>