pgsphere - pgsphere: + add license file + add pg_sphere_version()

Log Message:
-----------
+ add license file
+ add pg_sphere_version() function
# fix floating point issue in vector_cross

Modified Files:
--------------
    pgsphere:
        Makefile (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/Makefile?r1=1.4&r2=1.5)
        output.c (r1.2 -> r1.3)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/output.c?r1=1.2&r2=1.3)
        pgs_point.sql.in (r1.1.1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/pgs_point.sql.in?r1=1.1.1.1&r2=1.2)
        point.c (r1.1.1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/point.c?r1=1.1.1.1&r2=1.2)
    pgsphere/doc:
        install.sgm (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/doc/install.sgm?r1=1.4&r2=1.5)
    pgsphere/expected:
        init.out (r1.2 -> r1.3)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/expected/init.out?r1=1.2&r2=1.3)
        poly.out (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/expected/poly.out?r1=1.4&r2=1.5)
    pgsphere/sql:
        poly.sql (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgsphere/pgsphere/sql/poly.sql?r1=1.3&r2=1.4)