Compile of Test example is put into win32.mak of libpq.

Hi.

First:
I needed other programs, in order to test what always built independent libpq.dll.
Therefore, environment was considered variously. Then, I thought that a sample
program was helpful. They are written to the document.

Next:
I understood that test example could not compile by MinGW (gcc).
Furthermore, there was a problem of some MS-VC+. and, some difference was
in the document and the program. However, It is not a problem in the reason
a document is explanation in standard environment. probably.

testlibpq4.c does not have description in a document. and, a program comment
and operation were not in agreement...Therefore, a little change was given.
I thinks that it is enough, in order to show an example.

error happen before patch apply.
http://winpg.jp/~saito/pg_work/testlibpq2.c.error
http://winpg.jp/~saito/pg_work/testlibpq3.c.error
I was able to do the satisfactory test after
http://winpg.jp/~saito/pg_work/win32_i386_log.txt
However, only compile was performed by the reason AMD64 does not have test
environment..now.
http://winpg.jp/~saito/pg_work/win32_AMD64_log.txt

Please take this into consideration.

P.S)
As for me, this is very helpful by the reason lost psql.exe in win32.mak. !

Regards,
Hiroshi Saito