fix(igroup): Do not show GRP_ADDUSER menu if user has not the "modify" acl (refs #4658)
test(GroupAccount): Test insertDocument() on IGROUP with PDIR (refs #4658)
fix(GroupAccount): Disable edit control before calling RefreshDocUser() (refs #4658)

Disable edit control before calling RefreshDocUser() in postInsertDocument().
Merge pull request #1123 from eguaj/3.2-A4658

fix(igroup): Do not show GRP_ADDUSER menu if user has not the "modify" acl (closes #4658)