v1.5.0 release -- build system updates

Dear KIM Community,

I'm happy to let you know that I have just released openkim-api-v1.5.0.

This release updates the build system to improve the way the package is installed to standard system directories and provides for each user on the system to have their own personal set of Models that the KIM API can access. See the INSTALL file for details.

The change log entry is:
=== openkim-api-v1.5.0 =========================================================

* Documentation updates, including an extensive discussion of the installation
   process in INSTALL.

* Update examples to use KIM_API_file_init() and name their ".kim" file
   "descriptor.kim" in accordance with the new convention of the openkim.org
   processing pipeline.

* Deprecate KIM_API_init() and add KIM_API_file_init() to replace it as the
   primary openkim.org Tests should initialize the KIM API and specify their KIM
   descriptor files.

* Portability fixes for the make system

* Move away from naming various files based on the item (Model Driver, Model,
   Test) name. Instead establish standard names for each item type.

* Added Makefile.Version to provided the make system with version information
   and set policy (based on SemVer 2.0.0) for how, when, and why to update the

* Significant updates to the make system. Primarily associated with
   installation of the KIM API to a system-wide location, and its use once
   installed there.