parse options before downloading nwjs binary (since some of the nwjs binary prep depends on whether we're building a dmg)

If compiling an OSX dmg, don't try to change permission on a file which doesn't exist for that platform

don't build wiringPi
don't run dpkg-architecture
remove reference to AppMain.tcl

fix tar_em_up.sh to store binaries in the main repo directory so that the gitlab ci can upload them as artifacts, and change the ci config to find them

* fix typo introduced into tar_em_up.sh
* remove flext and rtcmix from LIB_TARGETS
* selectively compile disis classes on Windows
* use Program Files (x86) for win64

moved cwiid and all disis libs except disis_munger to externals/disis, and removed linux-specific build instructions from tar_em_up.sh

begin porting the disis_* dirs to a single library in externals/, starting with disis_phasor~.c.  We're just using the most recent version of pdlibbuilder to do the heavy lifting.

port agraef's commit from Pd-l2ork: Make 'tar_em_up.sh -B -n' do the right thing, by moving the extra staging done by 'make deb' into a separate 'debstage' target. commit 73bf25e1dd5bd2dd37e04e7e163855d440542e43

port aa6126adae5613d337cc71cee17b0078485dcc05 from Pd-l2ork: added temporary fix for rtcmix build until it is fixed upstream

port 78d634e8dc84b3c11611480000357efeea0b0027 from Pd-l2ork: fixed regression as per Albert's request

add 105f71eba94f47ccdbf344f16a29758909a265e5 from Pd-l2ork: better pulling of submodules (TODO: add wiringpi as a submodule)

port a49a2bbc138b34080f36ad3d091e57db6bb0e7ba from Pd-l2ork: fixed segfault caused by the latest commit. Now everything should work including the RPi3.

port 07081a7590bc80a65d0a3f9a6fd6fa3f3b16e777 from Pd-l2ork: introduced potential fix for spi issues on RPi3