Fix coding error in send loops (specify bit size of literal)

https://github.com/shirriff/Arduino-IRremote/issues/156

Improve output for recvDumpV2
Added my name to the contributors list (not 'cos I really care for the credit <whatever> but so people know who to "blame" [non-pejorative])
Moved the decode() function to the top of the source as it is likely to be edited the most

Added to changelog

Moved contributors to a different file