updated license information

git-svn-id: https://dev.geogebra.org/internal/moodle/moodle-qtype_geogebra/trunk@3399 872ce066-4876-4fca-a6fc-23b94bf576d1
Merged from trunk
updated license information [from revision 3399]

git-svn-id: https://dev.geogebra.org/internal/moodle/moodle-qtype_geogebra/branches/MOODLE_27_STABLE@3403 872ce066-4876-4fca-a6fc-23b94bf576d1
updated license information

git-svn-id: https://dev.geogebra.org/internal/moodle/moodle-qtype_geogebra/trunk@3404 872ce066-4876-4fca-a6fc-23b94bf576d1
Merged from trunk
updated license information [from revision 3404]

git-svn-id: https://dev.geogebra.org/internal/moodle/moodle-qtype_geogebra/branches/MOODLE_27_STABLE@3405 872ce066-4876-4fca-a6fc-23b94bf576d1