port b39417b3d4676fb3275aa31be934fe776718504c from Pd-l2ork: experimental improvements to the Linux build to make it compatible with Ubuntu 16.04

port e3e30ff94964fddd5764fd64391dcf8216354264 from Pd-l2ork: forgot to convert configure.in to configure.ac

The old path was /usr/local/bin, but I think Hans was manually adding the dlls there. If not we can use an ifdef to set this specifically for use with msys2

comment out some dlls for building on Windows with msys2 (we'll see if it turns out we need them later when testing)

*added lyon to default path
(ported manually, left out control file since it was ported in a previous manual port...)

*updated dependencies that reflect rtcmix~ external needs

*forgot to add two files

 *hopefully fixed the remaining conflicts between pd-extended deb and pd-l2ork deb

 *fixed potential package conflict with old pd-extended due to Gem includes. Moved them to /usr/include/pd-l2ork/Gem/ instead of /usr/include/Gem

remove pentium4 arch (I'm on a MacBook Air-- not sure if that would compile on some other Mac)

from pd-l2ork: 640d3c53ad8cd592b1d757b988e27d3ada2b1779

from pd-l2ork: b9cd12d16229acf3a66accc4ad0bdae03d96f19b

from pd-l2ork: a7f382e3d4ffd84c0e7246fdc2d24afca81784f9

 istalls[sic]."
 ee538990d34d4aea0b1757976d8e8dffbeb21a38

0e1938c2d6b3c460fb6eefd027c990fbb36078f9

*further improved naming convention for settings files (default.settings and user.settings), cosmetic improvements to the indexing prompt of the help browser dialog.

*updated file locations and made names more consistent across all folders (everything now uses pd-l2ok instead of pdl2ork). Placed user settings into ~/.pd-l2ork/ folder and renamed to simply settings, placed xapian search database for the browser inside the ~/.pd-l2ork folder.

*removed qt from autobuilds since qt5 is not standard in Ubuntu 12.04 and besides we need to update control files as well as online documentation

*improved installer to make it easier to recompile pd-l2ork when continuing development after building a snapshot deb or tarball installer (the pd folder will retain config script with the appropriate --prefix flag)