digital: Removed spurious XML
build: adding fstream include files for pedantic compilers.
qtgui: bringing in line with required Qt 4.4.

setGraphicsSystem was introduced in 4.5; doing a version check before its use.
Merge branch 'maint' of git.gnuradio.org:gnuradio into maint
qtgui: fixes a bug in the number sink to respect the update time.

Addresses issue #703.
qtgui: fixes a problem with the number sink when fed NaN or +/-inf.

Addresses issue #704.
volk: adding string.h to puppet for memset calls.
digital: Fix error in HDLC framer rejecting packets when falsely determined to be
"out of frame".
Merge remote-tracking branch 'bistromath/hdlc' into maint
Merge remote-tracking branch 'mbant/digital/spurious_xml' into maint
blocks: correcting use of mutexes in file_meta_sink.

the gr::block class has a d_setlock mutex that's appropriate for this use instead of creating another for the child class.
qtgui: fixed a bug in the constellation plots that didn't allow us to reduce the number of samples.
qtgui: replaced use of local mutex with d_setlock from gr::block.

Partial response to issue #706.
qtgui: got a little carried away removing local mutexes. SpectrumGUIClass is not a gr::block and so doesn't have a setlock.