pg-migrator - pg_migrator: Rename variables for clearity; move some

Log Message:
-----------
Rename variables for clearity;  move some items into structures.

Modified Files:
--------------
    pg_migrator/src:
        controldata.c (r1.6 -> r1.7)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/controldata.c.diff?r1=1.6&r2=1.7)
        exec.c (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/exec.c.diff?r1=1.4&r2=1.5)
        file.c (r1.9 -> r1.10)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/file.c.diff?r1=1.9&r2=1.10)
        info.c (r1.9 -> r1.10)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/info.c.diff?r1=1.9&r2=1.10)
        option.c (r1.10 -> r1.11)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/option.c.diff?r1=1.10&r2=1.11)
        pg_migrator.c (r1.19 -> r1.20)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/pg_migrator.c.diff?r1=1.19&r2=1.20)
        pg_migrator.h (r1.20 -> r1.21)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/pg_migrator.h.diff?r1=1.20&r2=1.21)
        relfilenode.c (r1.14 -> r1.15)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/relfilenode.c.diff?r1=1.14&r2=1.15)
        server.c (r1.9 -> r1.10)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/server.c.diff?r1=1.9&r2=1.10)
        util.c (r1.7 -> r1.8)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/pg_migrator/src/util.c.diff?r1=1.7&r2=1.8)