POM: bump to pom-imagej 2.49

This bumps several components to include and accommodate the new
App API, specifically the about(), prefs() and quit() methods.

This avoids a slew of ImageJ service dependencies being brought into
non-ImageJ contexts (e.g., those created using new
Context(SciJavaService.class)) due to the multiple AppEventService
implementations -- particularly the LegacyAppEventService which sucked
in the DefaultLegacyService which sucked in many other ImageJ services.