0026674: Performance regression in BRepExtrema_DistShapeShape in OCCT 6.9.0 in compare with OCCT 6.7.1

Creation the test case for current issue.

Added flag for single extrema computation. Now implemented only for parametric solver GenExtCC.
Default behavior of curve/curve solver in distmini command changed to "find one solution".

tests/bugs/modalg_6/bug26674

@@ -0,0 +1,37 @@
+puts "========"
+puts "OCC26674"
+puts "========"
+puts ""
+#################################################
+# Performance regression in BRepExtrema_DistShapeShape in OCCT 6.9.0 in compare with OCCT 6.7.1
+#################################################
+
+set max_time 1
+
+restore [locate_data_file OCC26674-face.brep] a1
+restore [locate_data_file OCC26674-shell.brep] a2
+
+dchrono cr reset
+dchrono cr start
+
+distmini dd a1 a2
+
+dchrono cr stop
+
+set log [dchrono cr show]
+
+regexp {CPU user time: ([-0-9.+eE]+) seconds} $log full z
+puts "$z"
+
+if { $z > ${max_time} } {
+    puts "Elapsed time of BRepExtrema_DistShapeShape is more than ${max_time} seconds - Error"
+} else {
+    puts "Elapsed time of BRepExtrema_DistShapeShape is less than ${max_time} seconds - OK"
+}
+
+regexp {([-0-9.+eE]+)$} [dump dd_val] full dist
+
+set expected_dist 0.0
+set tol_abs_dist 1.0e-07
+set tol_rel_dist 0.0
+checkreal "Dump of dd_val" ${dist} ${expected_dist} ${tol_abs_dist} ${tol_rel_dist}