distinct URI for suspend/delete

/users/?suspend=<username>  =>  /users/suspend/<username>
/users/?delete=<username>   =>  /users/delete/<username>
added possibility to delete users
added granting/revoking of admin privileges

any admin (username 'admin' or account_type 'admin') can toggle the
account_type of any other non-guest user from 'admin' to 'user' and vice-versa
the "real" admin (username 'admin') is of course unaffected
Merge branch 'master' into usermgmt
reapplied LDAP code to current upstream
setup.py: added 'python-ldap' to install_requires
auth.py: removed some trailing whitespace
forgot 2 lines in user.py
only display "reset password" link for non-external users
undid 1b93d9b583852c7c8e64fd938d02d0d26fc8cbab
only display LDAP settings if python-ldap is installed
Tools for sws2rst
Merge remote-tracking branch 'sagemath/master' into sws2rst
Trac 10637 reviewer patch

More accurate error message if BeautifulSoup is not installed
Merge branch 'master' into ldap
disable LDAP automatically if import fails
Merge branch 'master' into ldap
Merge branch 'master' into usermgmt
Merge branch 'master' into ldap
Merge branch 'master' into usermgmt