libowlps-client and libowlps-resultreader were never built as shared
libraries, therefore we set their version number to 1.0.
For stable releases, the rule is to increase the minor version number
when changes are made to the library without changing the API, and to
bump the major version number (soname) in case of API change.
In the development branch and for development point releases, the soname
should not be increased, even in case of API break. The minor version
number should be bumped instead.
Following this rule, libowlps' version number is bumped to 3.1, as some
changes were made since version 3.0.
Change the positioning.generate-reference-points option to offer
multiple choices (false, mesh, list, both) and add the
positioning.generated-points-list to allow the user to specify a list of
reference points to generate.