IPV6 complie fix.
Apply cache position on permission problem.

Calling a function with necessary permission will cause apply_cache to
be filled with a "non-exist" result, and later calls with enough
permission will still not be able to call it.

Fixed by explicitly return as runtime problem on access permission denied.
It also skip the cache filling on such errors.
Test and set std=c99 mode on supported platform.

Also setting Wextra in development mode.
Delete auto-generated files.
Correctly detect Linux and x86-64 environment.
Fix compile warnings
Fix overflow issue for TYPE_MOD_ARRAY.
Warning fixes, also I belive is 64bit lpc fixes.
Compile warning fixes
version 2.24.sunyc2
use INT_MAX for array size limit
Update testsuite config to correctly launch testsuite
logging improvement for testsuite.
LPC float literals is now double too, matching float variables.
Correctly handle 64bit defines.

Also expose standard limit __INT_MAX__, __INT_MIN__,
__FLT_MAX__, __FLT_MIN__ as predefine.
Adding a test case for LPC int/float correctness verification.

It will pass as long as it is stored as C 64-bit int & double,
as well as parser correctly parse constant literals.
Prevent int overflow if max_eval_cost is set high.
Fix benchmarking command in test suite.

And update motd to show two new commands.
Adding TODO list.
Fix comment for HEARTBEAT_INTERVAL in options.h