pgsql: Fix storage size for btree_gist interval indexes.

Log Message:
-----------
Fix storage size for btree_gist interval indexes. Fix penalty
calculations for interval and time/timetz to behave sanely for both
integer and float timestamps; up to now I think it's been doing
something pretty strange...

Modified Files:
--------------
pgsql/contrib/btree_gist:
btree_gist.sql.in (r1.12 -> r1.13)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_gist.sql.in.diff?r1=1.12&r2=1.13)
btree_interval.c (r1.5 -> r1.6)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_interval.c.diff?r1=1.5&r2=1.6)
btree_time.c (r1.8 -> r1.9)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_time.c.diff?r1=1.8&r2=1.9)
btree_utils_num.h (r1.4 -> r1.5)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_utils_num.h.diff?r1=1.4&r2=1.5)
pgsql/contrib/btree_gist/expected:
init.out (r1.1 -> r1.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/expected/init.out.diff?r1=1.1&r2=1.2)