Upgrade NameId array format.

Change all users of the nameId arrays to use 'Value' instead of
'value'. 'value' was the old name, but this is changed to 'Value' in
order to be consistent with other attributes.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@1654 44740490-163a-0410-bde0-09ae8108e29a