Block State
    BlockState refers to a block object without detailed step information.
    A block is rendered in XML as a nested <block> element containing all child blocks if there are any.
    A block can either be a composite block, meaning that it has nested child blocks, or a step block, meaning the block contains steps, but no child blocks.
    The steps information is not included by default, you need to request the stepblock through a rest call that explicitly returns the step block. 
See also StepBlockState, the version of <block> that also contains step information.
Attributes
- id
 - The ID of the block
 - state
 - The current state of the block:	
PENDING,EXECUTING,STOPPED,FAILING,FAILED,ABORTING,ABORTEDorDONE. - description
 - Textual description of the block.
 - parallel
 - Indicates if the block will execute in parallel
 
Child elements
- <block>
 - The nested blocks.
 
Example
<block id="1" state="PENDING" description="Deploying AnimalZoo-ear 1.0 on environment 0smallEnv0" parallel="false">
  <block id="1-1" state="PENDING" description="Deploying group default" parallel="true">
    <block id="1-1-1" state="PENDING" description="Deploying on container smallServer0"/>
    <block id="1-1-2" state="PENDING" description="Deploying on container smallServer1"/>
  </block>
  <block id="1-2" state="PENDING" description="Deploying group 1" parallel="true">
    <block id="1-2-1" state="PENDING" description="Deploying on container tinyServer0"/>
    <block id="1-2-2" state="PENDING" description="Deploying on container newServer0"/>
  </block>
</block>
