[beeswax] Configure support for Hive Server2 LDAP authentication

When Hive server2 is setup with LDAP authentication (in hive-site.xml)

<property>
<name>hive.server2.authentication</name>
<value>LDAP</value>
</property>

At the hue.ini side, set up the following:

[desktop]
ldap_username=hue // username for Hue to authenticate to Hive Server
ldap_password=xxxxxx // password for Hue to authenticate to Hive Server

Hue still seems not be able to work with LDAP of Hive server2.

From hue code apps/beeswax/src/beeswax/server/hive_server2_lib.py :

HS2_MECHANISMS =

{'KERBEROS': 'GSSAPI', 'NONE': 'PLAIN', 'NOSASL': 'NOSASL'}

...
use_sasl = hive_mechanism in ('KERBEROS', 'NONE')
mechanism = HiveServerClient.HS2_MECHANISMS[hive_mechanism]

It doesn't handle LDAP authentication. "NONE" has to be used in hive-site.xml for LDAP authentication. It would be nice to handle LDAP authentication mode properly at Hue side for Hive Server2