0031756: Data Exchange - broken parsing of STEP entity in case of missing last parameter

- Parser is corrected to handle case of missing arguments properly (report error without corruption of the next entity)
- Added counter of entity arguments for appropriate error messages
- Plain C tools and data structures (recfile.*, stepfile.*) are converted to C++ class (StepFile_ReadData) to avoid use of static variables, so that reader can be safely used in a multi-threaded environment

tests/bugs/step/bug31756

@@ -0,0 +1,19 @@
+puts "================"
+puts "0031756: Data Exchange - broken parsing of STEP entity in case of missing last parameter"
+puts "================"
+puts ""
+
+pload OCAF
+
+stepread [locate_data_file bug26451_Test_STEP.stp] a *
+
+set entityInfo1 [ entity #71919 ]
+
+if { [regexp "'',83477:#84041,83477:#84041,#0,#0" $entityInfo1] != 1 } {
+   puts "Error : wrong arguments of parsed record"
+}
+
+set entityInfo2 [ entity #71920 ]
+if { [regexp "71356:#71920 = FILL_AREA_STYLE" $entityInfo2] != 1 } {
+   puts "Error : wrong record, parser skip record"
+}