Lighttpd

Thanks for caring about code quality :)

• lemon.c is just a parser generator and is used only to build lighttpd. I have no intention to do anything more than really super trivial and obvious fixes. (Also you don't need to check pointers before calling free)
• the other checks should be done when the values gets assigned; force_assert is always active at runtime, and I don't want to check every pointer with force_assert before using it.
  Also force_assert just makes it crash with a nicer error message; dereferencing NULL pointers (or near NULL in case of small structs like buffer) should always trigger a segfault.