Improvements to mce tools

The evdev_trace utility no longer requires full paths, for example "/dev/input/event1"
can be shortened to "event1" or just "1". When listing device info, active/down
switches/buttons are indicated with '*'.

The huge main() function in the mcetool is split into smaller chunks. Also the
command line options are now processed in the order given, which allows more
control over what is done without using multiple invocations of mcetool.