LEAP/SLE15: TLS, history explorer and other features.

Features:

• Allow also users in haclient to view history explorer (#213)
• Disable TLS 1.0 and TLS 1.1 by default . SLE15 , see (https://github.com/ClusterLabs/hawk-apiserver/releases/tag/0.0.4) for further information

Bugfixes:

• handle properly in the webui when a Cluster resource has the same name of a node of cluster (#211)