Port pd-l2ork upstream commits from Dec 7, 2015 improving the handling of $ substitutions in GUI elements. Also fixes #195.

Get rid of some really annoying legacy Tcl commands in the core. As long as we don't have any LED indicators in the console window, show an error for audio dropouts instead. Also get rid of some debugging messages in the pddp.

port c6771297b6f03887034c5f121d3dbf701623ab87 from Pd-l2ork: the big Vanilla forward port won't compile without this commit

(selective port-- didn't include the logic related to the x_selected member
*fixed bug reported by Gilberto in http://disis.music.vt.edu/pipermail/l2ork-dev/2015-January/000676.html

"Quick-n-dirty" means the "//" comment itself isn't indented.

removed the array listview code from g_array.c.  Seemed pretty straightforward to prune, but should probably test to make sure there aren't any obscure regressions

Fix nasty bug with array name not updating properly on its graph, plus a more trivial bug with the canvas properties not getting updated properly

fix feature for putting array in existing graph
add a delete checkbox for graphs with multiple arrays

*fixed inconsistent display of array styles between pd-l2ork and vanilla. LATER consider cleaning this up by adjusting g_canvas.h instead of all these workarounds.

fixed bug with 8x8 click "hotspot" not working correctly on x-axis of garrays

*fixed proper opening of paths with spaces ia unique check

*fixed remaining problems (hopefully) with 2 arrays drawn in the same gop (need to test with more than 2 arrays?)
*bug for Jonathan--bar graph draws from top down, as opposed from bottom up when opening array gop

*improved fittograph for multiple arrays (still needs some work)

*further improvements on the garray selection and redraw--fixed garray contents not remaining selected after dialog properties have been applied
*still need to explore problems with multiple arrays in a single GOP

*fixed segfault when resizing array via dialog (regression from May commit). Still need to work on fittograph logic for situations where there are multiple arrays in the same GOP

*added recursive checking for when objects are selected to properly reselect arrays nested inside GOP subpatches/abstractions. This is important because the implementation should work for any level of depth. Later consider making this a more universal check should such prove necessary (I think once we move away from redrawing the array every time a point is moved, all this will become moot)

*added comments with future TODOs

- nested plots display properly
- plot is vis'd and unvis'd properly when deleting plot or struct
- commented out ugly plot_displace hack-- multiple plots should work just fine
- separated out garray dependencies into class "old_plot".  This way the changes I made don't affect garrays.  _Very_ ugly hack, but it was pretty simple to implement and will be easy to remove later.
- no crashes when non-existent arrays are entered into a [struct] that has scalars hanging around
- template_cancreate ported from 0.45
- added a function to get the offending struct (to use with "Find last error").  Not using it yet, though.
+ For creating scalars using an object box:
- scalar must have initial "float x float y" fields, in that order.  This means you can't accidentally type the name of the hidden garray structs and create a scalar.  (Nor any other structs that only have a "y" field, etc.)
- broken object box returned if the struct has a bogus array template.  (Although currently I'm just refusing to create such a struct.)