Named pipes - implement scripts for new test cases

[nicholaides]

This PR adds test cases for reading from and writing to named pipes.

• [x] Add test cases streaming_pipe_in, streaming_pipe_in_and_out,
• [x] Add scripts for all the languages for the new test cases

The main things to note:

• writing to stdout and to a named pipes is usually buffered, which can cause the output to never be delivered because it's waiting for the buffer to fill up or for the the file/pipe to be closed.
• reading from a named pipe is like reading from a regular file except for that regular files have all their content available immediately, whereas a named pipe will only have content available as it gets added to the pipe by the process that's writing to the pipe. Therefore, functions that try to read a whole file into a string will hang because it will be waiting indefinitely the named pipe to give it more data.