success to comile libevent
[libevent, FIX] success to 'import("libevent")'.
+ and success to 'Libevent e = new Libevent();"
[test] 1st step for "libevent_glue.k".
has no error this konoha script.
my konoha test code
add libevent_event_glue.[ck], and successt to compile
add "System.event_add()" method,
and success to compile.
add "System.event_del()" method,
and success to compile.
add "Libevent.dispatch()" method,
    and success to compile.
add constant declaration for event_add().
move 'kDate' declaration to header file.
has no statement error by minikonoha.
fixed mistake.