* Add StringEx.ToByteArray(...)
* Add Serialization.SerializeDataItem(DataItem)
Supports StringEx VarType or offloads to SerializeValue method.
* Use SerializeDataItem in S7WriteMultiple
* Assume string length without header in StringEx.ToByteArray
VarTypeToByteLength already assumed that StringEx declared count for
the number of characters without the header, this now matches that
behavior.
* Add unit tests for StringEx conversions
* Fix incorrect value passed to Encoding.GetBytes
The length must actually be within string limits.
Note: This keeps the old methods to be backward compatible.
Note: Unforntunatly a lot of whitespace fixes, refactoring and other trivial stuff is
included. It was to hard to split of in a seperate commit.
Note: Async methods does not use exactly the same structure/signature as the
existing methods. "Out" parameters like ReadClass and ReadStruct instead
returns the struct in tuple. Async methods also rely on exceptions
instead of ErrorCodes to communicate exception states to calling client.
* Use TcpClient and use Async methods (ReadAsync/WriteAsync)
* Implemnt async methods for all existing methods
* Implemnt existing methods using tcpclient.
* Split Plc.cs in more files. (Common, Async, Sync, Helpers)
* Mark old methods as Obsolete
* Split tests in two files
* Implement Async tests
