channels: setting up callbacks for most dynamic channel model parameters in GRC
analog: fixed Linux assumption, added ifdef to use rand() instead of lrand48() when using MSVC
qtgui: fixed issue with newer versions of QT.

When creating the qApplication in the block, we have to make sure argc>0, argv contains at least one valid character (\0), and they exist over the life of the application.
digital: cleaned up pfb_clock_sync blocks and make sure fff and ccf doing the same things.

Updated QA code to tighten up specs because of better convergence now.
Merge branch 'master' into next
Merge remote-tracking branch 'ncorgan/analog/lrand48_windows_ifdef'
Merge remote-tracking branch 'osh/master'
Merge branch 'master' into next
cmake: update revision to 3.7.1.1
Merge branch 'maint'

Used merge strategy -s ours to skip release commit.
cmake: update revision to 3.7.2
cmake: update revision to 3.7.3git
Merge branch 'master' into next

Use merge strategy -s ours to skip release commits.
fft: fixed logpwrfft.py to import new C++ window properly from fft_swig (fixes issue #609 reported by Sylvain Munaut).
Merge branch 'master' into next
fft: put include protections around window.h (fixes issue #610 reported by Sylvain Munaut).
Merge branch 'master' into next
Update revision to 3.7.2

(moved 3.7.2 release to this commit)
Update revision to 3.7.3git
Merge branch 'master' into next

Used merge strategy -s ours to skip release commits.