Add parameter for end-of-message byte

[diogok]

You can specify a different message terminator byte, defaulting to '\n' to keep backwards compatible.

[firstrow]

Thanks for PR. I will do review/test and then merge!

[tech10]

I could see this being a useful feature, I would be happy to merge conflicts and submit a pull request for the updated library, as changes have been made since this pull request was made.