maint: Follow Octave conventions for use of semicolon in BIST tests. * testfun.txi: Document Octave conventions for use of semicolon in BIST tests. * cellfun.cc, ellipj.cc, file-io.cc, gcd.cc, hash.cc, nproc.cc, utils.cc, fftw.cc, ov-usr-fcn.cc, oct-parse.in.yy, md5sum.m, wavread.m, wavwrite.m, cplxpair.m, rat.m, im2double.m, rref.m, stem3.m, rotate.m, pchip.m, blackman.m, hamming.m, hanning.m, spectral_adf.m, spectral_xdf.m, assert.m, fail.m, etime.m, build-sparse-tests.sh, classes.tst, ctor-vs-method.tst, index.tst, io.tst, struct.tst: Follow Octave conventions for use of semicolon in BIST tests.

--- a/libinterp/corefcn/ellipj.cc	Fri Apr 01 16:03:29 2016 -0700
+++ b/libinterp/corefcn/ellipj.cc	Fri Apr 01 18:16:01 2016 -0700
@@ -831,7 +831,7 @@
 %!error ellipj (1)
 %!error ellipj (1,2,3,4)
 %!warning <required value 0 <= M <= 1> ellipj (1,2);
-## FIXME: errors commented out untill lasterr() truly returns the last error.
+## FIXME: errors commented out until lasterr() truly returns the last error.
 %!#error <M must be a scalar or matrix> ellipj (1, "1")
 %!#error <U must be a scalar or matrix> ellipj ("1", 1)
 %!#error <U must be a scalar or matrix> ellipj ({1}, 1)