Typo in attachYieldFunc.cpp

[wwatson4506]

In TeensyHelpers I could not compile attachYieldFunc.cpp. The compiler said it could not find
'Eventresponder.h'. That was because the EventResponder include filename is 'EventResponder.h'.
The 'r' in the filename was in lower case instead of upper case. I fixed that and it compile ok.

Thanks for creating these great libraries. I am having a lot of fun testing them with MSC. I have made some good progress with using them.

Warren

[luni64]

Thanks, should be fixed