Added two commands to WA to record and replay input events using revent.
As part of this also added the ability to get a device model from
android and linux device. This may need to be improved in the future.
The struct used to read events is being padded when built for 64
bit platforms. The padding has been made explicit in the struct, and
matching padding was added when writing the events during recording.
Then number of input event files was being written as a size_t but read
as an int by revent. These types have different sizes with 64bit GCC,
causing revent not being able to replay recorded files. This comint
updates revent to use size_t when both reading and writing.
