v4.0

Update README.md

v2.51 Improved command prompt parsing (now ignores '\n')

We now ignore the \n character when parsing characters from the command prompt. This makes it easier to create code on a microcontroller that correctly controls OpenLog. Previously, println or sprintf commands were adding a \n to the end of the string that would confuse OpenLog. One way around this if you have previous versions is this
 sprintf(buff, "new blah.txt\r");
 Serial.print(buff); //No println, use \r in string instead

Also - added a CommandTest sketch to demonstrate how you can control OpenLog from a microcontroller / automate the command prompt