Switch to BASE 3.15

[Nicklas Nordborg]

Related to #1120 but added as a separate ticket since it also requires other changes that are not related to the Apache POI.

[Nicklas Nordborg]

In 5363:

References #1131: Switch to BASE 3.15

Change to BASE 3.15. Fixed compilation error that are due to source-code incompatibilities related to generic return type parameters: ​http://base.thep.lu.se/chrome/site/latest/html/appendix/incompatible.html#appendix.incompatible.3.15

[Nicklas Nordborg]

In 5364:

References #1131: Switch to BASE 3.15

Getting rid of calls to deprecated methods.

[Nicklas Nordborg]

In 5590:

References #1131: Switch to BASE 3.15

Switched to BASE 3.15.2 since we need the Tag importer to import barcodes.