add comment and short README to ngspice shared

example for reading XSPICE data

visualc/ng_shared_xspice_v/README.xspice

@@ -0,0 +1,8 @@
+README.xspice
+
+Compile shared ngspice with Debug and 64 bit
+
+Compile the example caller with Visual Studio
+using ng_shared_test_v.sln.
+
+Start the example with calling ng_shared_start.bat

visualc/ng_shared_xspice_v/ng_shared_start.bat

@@ -1,3 +1,4 @@
+REM start ngspice example returning XSPICE data
 cd x64
 start /B .\Debug\ng_shared_test_v.exe
 PAUSE