move rSYMBOLs from pic_state to codegen_state
add sSYMBOLs to pic_state
add analyzer prototype
arena management
fix some bugs
typo
change lookup_var API
initialize with global scope
remove unused properties
Define the type of marking flags as unsigned int.

We could define it as _Bool since we are going to use C99, but unsigned
int is more portable (even in C89!) and extensible (when we decide to
use tri-color marking GC.)

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Merge pull request #23 from omasanori/iso-c-mark

Define the type of marking flags as unsigned int.
add pic_list_ref
add pic_compile
increate gc header alignment size
add pic_list_ref and pic_list_tail
add pic_append
impl list-ref and list-tail as C functions
replace length/reverse/append impls with c functions
replace list impl by scheme with impl by C
replace cxxr and list? impls by scheme with ones by C