pg-migrator - src: Rename lots of identifiers, for clarity.

Log Message:
-----------
Rename lots of identifiers, for clarity.

Modified Files:
--------------
    src:
        controldata.c (r1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/controldata.c.diff?r1=1.1&r2=1.2)
        exec.c (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/exec.c.diff?r1=1.3&r2=1.4)
        file.c (r1.5 -> r1.6)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/file.c.diff?r1=1.5&r2=1.6)
        info.c (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/info.c.diff?r1=1.4&r2=1.5)
        option.c (r1.2 -> r1.3)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/option.c.diff?r1=1.2&r2=1.3)
        pg_migrator.c (r1.62 -> r1.63)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/pg_migrator.c.diff?r1=1.62&r2=1.63)
        pg_migrator.h (r1.10 -> r1.11)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/pg_migrator.h.diff?r1=1.10&r2=1.11)
        relfilenode.c (r1.8 -> r1.9)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/relfilenode.c.diff?r1=1.8&r2=1.9)
        server.c (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/server.c.diff?r1=1.3&r2=1.4)
        util.c (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pg-migrator/src/util.c.diff?r1=1.3&r2=1.4)