Fix warnings when !PIC_ENABLE_READLINE.

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Add (import ...) to etc/tak.scm and t/*.scm.

Note that this commit only fixes 'unbound variable' errors. For now
t/dynamic-wind.scm, t/exception.scm and t/ir-macro.scm seem buggy on my
Linux (amd64) machine.

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Include string.h and stdlib.h at all time.

Even if readline support is disabled, some functions declared in
string.h and stdlib.h are used. (e.g. strlen and exit)

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Merge pull request #10 from omasanori/fix-import

Add (import ...) to etc/tak.scm and t/*.scm.
Merge pull request #9 from omasanori/without-rl

Fix warnings when !PIC_ENABLE_READLINE.
Merge pull request #8 from omasanori/fix-include

Include string.h and stdlib.h at all time.