Many Fixes and Improvements

[rafaelsc]

• Use netstandard2.0 to be compatible with net48 and netCore.

• Fix Rets Authentication on net48 (HTTPClient from net48 and netCore have different behavers)

• Fixes

  • Photo ID can be String by the specification
  • Allow bigger MaximumLength
  • Photo Get Object fixes when the server return only one photo result.

• Improvements

  • Request
    • Allow have a RAW rests query, that will be used instead the generated query by the Parameter Group
    • Allow Request have Offset to return the next page of results.
    • Allow Request the result count. (Total Server Count of a Query. (No data, just the number of results will be available)
    • Requests can be cloned.
  • Result
    • Allow SearchResult can tell if more Results available on the server after a result. (Server return paginated results)
    • Allow SearchResult return the Total Server Count of a Query. (No data, just the number of results will be available)

• Client

  • Add IsConnected and if the Connection was successful.

• Other

  • Implements IEnumerable for Library Collections.
  • Add Rests 1.9 version
  • Other improvements

• Fix Typo

• Refactor

• Code Format

• Code Clean Up

• Update decencies