add cleaning code once module init failed: fix bug of dangling handlers
replace kprobes with kretprobes to instrument syscall exit
increase maxactive of kretprobe to avoid misses
merge upcall/downcall: don't differentiate begin_/end_
enable remote vm writing in mem_introspect
enable return value rewriting in downcall
remove syscall indirect args rewriting from kernel
fix param order mistake at kzalloc (sting_kernel.c)
remove redefinition of pt_regs: use userspace ones
fix memory leak at msg allocation inside kernel
Merge branch 'master' of github.com:hvijay/netlink-test into experimental

Conflicts:
	kernel/sting_kernel.c
	user/sting_user.c
add initial support for victim's stack unwinding
fix memory leak and redundant unrolling in entry_helper
fix fd overflow bug and export get_area in entry_helper
fix compile errors for sting.ko
fix compile errors for sting.ko