DS-1622 Porting of the Login As feature to JSPUI
Turn xmlui/jspui.user.assumelogin property to the new webui.user.assumelogin, add custom jsp error to show no loginas action reason
Add link to return at epeople admin page, Add throw only authorizeexception, Show custom errorpage in the case of superadmin loginas superadmin
Add one error jsp with only a message, remove i18n for authorize exception message
Merge pull request #1 from lap82/DS-1622

[DS-1622] Uniform property xmlui/jspui in webui.user.assumelogin
Cleanup: this jsp is not an errorPage
Logout from a loginAs user will relogin the previous user
Merge pull request #286 from abollini/DS-1622

DS-1622 Porting of the Login As feature to JSPUI