Fix the issue #62 in the branch DEV

[mniak]

Create method Read(StreamReader) in the class FixedLengthFileMultiEngine and exposes it in the IFlatFileMultiEngine interface

[mniak]

The build failed, but it's not caused by the changes I made.
AppVeyor says that nuget restore failed, but as you can see, I've not changed anything related to NuGet.

Error: 12/26/2017 1:37:07 PM: 
 +                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [<<==>>] Exception: Exec: Error executing command  .$nuget restore $solution_path .
ERROR CODE: 1
Command exited with code 1

[mniak]

Tried to trigger build again but still not working.
I dont know what is happening but the code is fine

[niemyjski]

I'm not sure if this should be part of the contacts. We already have the ability to pass in a stream.

[mthamil]

I actually would like the feature as well. I needed to use a custom StreamReader implementation for reading my files and ended up downcasting the engine to use that overload.