Multiple fixes and updates:

(1) Fixed an error that was introduced in version 8.3.590 with
    a patch that should have been applied only for the case of
    BJT devices, and not for MOSFETs.  The patch will cause
    devices generated by "device mosfet" or "device asymmetric"
    to be read incorrectly from a .ext file during "ext2spice".
(2) Fixed an error in the tech file reading, where using CDL
    parameters on a capacitor device would cause the tech file
    loader to print an error message.  The parsing was correct
    and only the message should not have been printed.
(3) Added a new feature with the new command option "extract
    do unique".  This replaces the "extract unique" command by
    running the same code within the extraction, but has the
    additional effect of reverting the label changes afterward.
    This prevents the user from inadvertently writing the
    altered labels back to the database file.

commands/CmdE.c

@@ -930,6 +930,7 @@ cmdExpandFunc(
 #define	DORESISTANCE	6
 #define	DOLABELCHECK	7
 #define	DOALIASES	8
+#define	DOUNIQUE	9
 
 #define	LENCLEAR	0
 #define	LENDRIVER	1
@@ -977,6 +978,7 @@ CmdExtract(
 	"resistance		estimate resistance",
 	"labelcheck		check for connections through sticky labels",
 	"aliases		output all net name aliases",
+	"unique			ensure unique node names during extraction",
 	NULL
     };
     static const char * const cmdExtLength[] =
@@ -1280,6 +1282,7 @@ CmdExtract(
 		TxPrintf("%s resistance\n", OPTSET(EXT_DORESISTANCE));
 		TxPrintf("%s label check\n", OPTSET(EXT_DOLABELCHECK));
 		TxPrintf("%s aliases\n", OPTSET(EXT_DOALIASES));
+		TxPrintf("%s unique\n", OPTSET(EXT_DOUNIQUE));
 		return;
 #undef	OPTSET
 	    }
@@ -1309,6 +1312,7 @@ CmdExtract(
 		case DORESISTANCE:	option = EXT_DORESISTANCE; break;
 		case DOLABELCHECK:	option = EXT_DOLABELCHECK; break;
 		case DOALIASES:		option = EXT_DOALIASES; break;
+		case DOUNIQUE:		option = EXT_DOUNIQUE; break;
 		case DOLOCAL:
 		    /* "extract do local" and "extract no local" are kept for
 		     * backwards compatibility, but now effectively implement