Remove hard dependency on Qt plugins; make their resolution optional. Without this, most of Carbide fails to load if any Qt plugin is missing.
bin.includes = plugin.xml,\
META-INF/,\
html/,\
index/,\
uiqTOC.xml,\
tocConcepts.xml,\
tocReference.xml,\
tocRelease.xml,\
tocStart.xml,\
tocTasks.xml,\
reference/,\
book.css