Rename the arithmetic operations of fixnum type
Fix a bug in function `make_wstring' when increasing the index
Implements a EQ instruction
Loads the init file, compiles the expressions in it and run the compiled code.
Optimize the tail recursion in `read_object' as goto
Change the use of `port_read_char', `port_ungetc' and `find_or_create_symbol'

Let the `find_or_create_symbol' copy its argument by
itself. Therefore, the caller of this function is able to free the
memory allocated for passing to it.
Reimplements the `eval_proc' by compiling and executing
Add a special operator `macro' to define anonymous macro object

This operator is something like `lambda'. The macro can not be called yet.
Reverse the order of pushing arguments onto stack

修改了参数入栈的次序。尽管参数仍然是从左往右地求值，但却是从右往左地压栈。
Update the argument retrieving procedure of PRIM2

交换了arg1和arg2的初始化顺序
Add a `index' field into the vector definition

index表示下一个可以被设置的位置的下标
Implements four vector-related functions

is_vector_full: 检测向量是否再也无法放入新的元素
is_vector_empty: 检测向量是否不含有任何元素
vector_push: 将元素以后进先出的方式存储在向量中
vector_pop: 将上一次用push方式存储的元素弹出
Reverse the order of argument retrieving in IADD, ISUB, IMUL and IDIV.
Add the error checking into `vector_push/pop'
Use a vector instead of list for being the stack in virtual machine

And there's a lot of modification and bug fixings.
Fix a bug in PRIM3

The retrieving order is reversed.
Fix a bug in `eval_proc'

The third argument in last expression must be global variable `vm_stack'.
Fix a bug in `load_init_file'

The third argument of `run_compiled_code' calling must be `vm_stack'.
Merge branch 'feature-vector-stack' into develop
Misc