Close HOT template files after read
Close HOT template files after read

Previously get_base_nest_hot_dict() used by tacker-conductor
opens and reads HOT template files but does not close them.
As a result, tacker-conductor will reach the limit of open
file descriptor while it is running long time.

This patch fixes to close HOT template files after read
them.

This patch makes some clean-ups too.
* use existing method to make path construction and make it easy to
  understand.
* remove _get_base_hot_dict() because it was replaced to
  get_base_nest_hot_dict() and is not used anywhere now.
  And it is considerd that it will not be used any more.
* remove meaningless array to tupple translation.
* same bug fix and clean-ups are applied in the same file.

Closes-Bug: #1913978

Change-Id: I6ffdadc196cf2ddcec3625c6bd99b5133e37af4b

stackforge/tacker,stackforge/tacker,openstack/tacker,openstack/tacker,openstack/tacker