sp_cap() / cube() incompatability?

[PKeller34]

Where is the correct place to report bugs for BOSL2?

The following code produces an assertion failure:

`
include <BOSL2/std.scad>
include <BOSL2/bottlecaps.scad>

sp_cap(38,400,2, top_adj=-10);
cube(100,100,7);`

The error is:

`ERROR: Assertion '(num_defined([center, anchor]) < 2)' failed: " Cannot give both center and anchor" in file ../../libs/openscad/BOSL2/shapes3d.scad, line 64

TRACE: called by 'cube' in file bottlecap.scad, line 18`

Note top_adj is set to a negative value. Running sp_cap(38,400,2, top_adj=-10); by itself had the interesting effect of raising the thread out of the body of the cap. But BOSL2 doesn't complain about that:-) Bounds checking in BOSL2 seems to be prett robust in general, but this one either slipped through or hints at some other error in the code. (NOTE: See separate post on a variant of this crashing due to a syntax error in BOSL2.)