Improve configury for finding Linux <asm/alternative.h>.

Old configury did not find it on this 3.8 box.
Linuxmodule: Linux has changed the format for KERN_ALERT, etc.

Use those constants instead of hand-coded <1>, <2>, etc.
Linuxmodule: Use kthread_create.

Rather than kernel_thread. And with this we can run on Linux 3.8.
Email address updates.