Removing dead code

[atsju]

I propose to remove dead code.

I do not want to remove debug code or things like that. Just code that is here and is really not needed.

Here are garbage collection log and map file to help find unused sources
logGC.txt
output.map.txt

Top reproduce enable garbage collection:

QMAKE_CXXFLAGS += -ffunction-sections -fdata-sections
QMAKE_LFLAGS += -Wl,--gc-sections

For map files
QMAKE_LFLAGS += -Xlinker -Map=output.map
For the log:
QMAKE_LFLAGS += -Wl,--print-gc-sections

some useful commands:

grep -o '_Z[A-Za-z0-9_]*' outputUnused.map.txt | while read sym; do echo "$(c++filt $sym) $sym"; done >demangled.txt

[atsju]

fixed in #244