readme: kpatch is an infrastructure, not a tool
readme: taint clarifications
kmod/core: checkpatch and sparse fixes

- checkpatch doesn't like the FSF address since it's subject to change
- checkpatch doesn't like strings split by line
- whitespace fix
- sparse suggested to change some variables and functions to static
kmod/core: update a few comments

- update the file description comment to be a little more accurate and
  concise
- s/trampoline/ftrace handler/
Merge pull request #162 from jpoimboe/lkml

a few style fixes