crush-initial-weight config option does not work when set to 0

[Sandor Zeestraten]

# Versions
juju 2.3.4
ceph-osd rev. 259

# Issue
The crush-initial-weight config option does not work when set to 0 even though 0 is a valid value.

Example: `juju config ceph-osd crush-initial-weight=0`

# Cause
The Jinja template for ceph.conf only renders the config flag when it is non-zero.

https://github.com/openstack/charm-ceph-osd/blob/189e7620c07d81c5fdaa2c680c51ffd2d29f168b/templates/ceph.conf#L36

{%- if crush_initial_weight %}
osd crush initial weight = {{ crush_initial_weight }}
{%- endif %}

[Frode Nordahl (fnordahl)]

Review: https://review.openstack.org/#/c/561456/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/561456
Committed: https://git.openstack.org/cgit/openstack/charm-ceph-osd/commit/?id=5ea1973062a55af4d5c41da226d3d110b2b85ff6
Submitter: Zuul
Branch: master

commit 5ea1973062a55af4d5c41da226d3d110b2b85ff6
Author: Sandor Zeestraten <email address hidden>
Date: Sun Apr 15 13:13:22 2018 +0200

    Render crush-initial-weight option if set to 0

    Fixes the conditional in the ceph.conf template so it renders the
    crush-initial-weight config option if set to 0.

    Change-Id: Iaecbdf52bd3731effa3132e61364918407116dbe
    Closes-Bug: 1764077

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/18.02
Review: https://review.openstack.org/561565

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/561565
Committed: https://git.openstack.org/cgit/openstack/charm-ceph-osd/commit/?id=63a1fe3ac79311be35783e5dd32ad59c87cc4d1d
Submitter: Zuul
Branch: stable/18.02

commit 63a1fe3ac79311be35783e5dd32ad59c87cc4d1d
Author: Sandor Zeestraten <email address hidden>
Date: Sun Apr 15 13:13:22 2018 +0200

    Render crush-initial-weight option if set to 0

    Fixes the conditional in the ceph.conf template so it renders the
    crush-initial-weight config option if set to 0.

    Change-Id: Iaecbdf52bd3731effa3132e61364918407116dbe
    Closes-Bug: 1764077
    (cherry picked from commit 5ea1973062a55af4d5c41da226d3d110b2b85ff6)