Author: Eric Merrill
MDL-48618 gradebook: Only use individual min/max for aggrigate grades
http://git.moodle.org/gw?p=moodle.git;a=commit;h=0624b774d0464a104775fc3ad8173dc519d5f03b
http://github.com/moodle/moodle/commit/0624b774d0464a104775fc3ad8173dc519d5f03b
+ 2.9 en [minmaxupgradedgrades,core_grades]
+ 2.9 en [minmaxupgradefixbutton,core_grades]
+ 2.9 en [minmaxupgradewarning,core_grades]
+ 2.9 en [upgradedminmaxrevertmessage,core_grades]