Display the word [default] next to the default teiid server

* Should the servers view contain multiple servers, display [default]
  next to the name of the teiid server that has been selected as the
  default
TEIIDDES-1550: Fix isFunction and isExpression methods

* Incorrect return values for some symbols for methods isFunction and
  isExpression.

* Mitigate by just including in LanguageObjectImpls and test delegate
  for whether its a Function and Expression respectively.
TEIIDDES-1550: Fix MappingDocument hierarchy for both runtime clients

* MappingDocumentImpl should extend MappingNodeImpl

* Adds load mapping document from input stream method to
  document factory

* Adds clone methods to each MappingNodeImpl class and
  sub-classes
TEIIDDES-1550: Introduce query node api for query plans

* Query plans used by the metadata interface are encapsulated in
  QueryNode.
TEIIDDES-1550: Expand the IQueryMetadataInterface

* More methods required to be exposed in order to correctly
  process transformation queries.
Merge pull request #74 from phantomjinx/master

TEIIDDES-1550