Fix a typo bug in `to_fixnum' and `to_character'
Establish the call-N policy
Change the name of `gen_callN' to `gen_primN'
Implements a basic framework for defining primitives without standard interface
Converts more primitives into non-standard interface form
Converts the arithmetic primitives
Finished the character and string data types part
Finishes the string and symbol type parts
Converts all existing primitives into non-standard interface form

The function `apply' hasn't converted yet. I guess all the converted
primitives is OK even though I don't test them.
Remove the primitive function `apply'

Maybe it's useless in a Lisp-1 language
Merge branch 'feature-all-prim-ins' into develop
misc
Add a trivial support for UTF-8 encoding
Add a primitive function for reading a byte from input port
Reimplements the function `read_char' for reading any utf-8 character
Delete some unnecessary comments in file `proc.c'
Do in file `object.c' as in file
Reimplements the C code for library function `string-ref'

Now the C function `string_ref' is able to process the UTF-8
character, although it cost O(n) time complexity.
Add a trivial support for constructing a string contains UTF-8 characters
Fix a bug in function `init_wchar'

The original length computation is wrong and cause too much copying of
characters from parameter `bytes' --- The `init_wchar' should assume
its argument to be an array of bytes, and these bytes makes a complete
UTF-8 encoding of an character.