ENH: ParameterSerializer: Improve escaping of the JSONModuleDescription

The JSONModuleDescription did not escape the already escaped quote marks
correctly, causing build error:

error: expected ';' after top level declarator
"  \"Default\" : \"\\"1\\"\",\n"

Escaping the escape character fixes this. A parameter with a string
default with quotes is also added to testing to make sure that this works.

Reported-by: Andrey Fedorov <fedorov@bwh.harvard.edu>
Tested-by: Andrey Fedorov <fedorov@bwh.harvard.edu>
Thanks: Andrey Fedorov <fedorov@bwh.harvard.edu>

Author: johan-andruejol

GenerateCLP/GenerateCLP.cxx

@@ -468,6 +468,16 @@ void GeneratePre(std::ostream &sout, ModuleDescription &, int argc, char *argv[]
 }
 
 #ifdef GenerateCLP_USE_SERIALIZER
+void ReplaceCharacter(std::string& line, char character, const std::string replacement)
+{
+  size_t position = line.find( character );
+    while( position != std::string::npos )
+      {
+      line = line.replace( position, 1, replacement );
+      position = line.find( character, position + 2 );
+      }
+}
+
 void GenerateJson( std::ostream & sout,
   itk::SEMModuleDescriptionSerializer::Pointer & serializer )
 {
@@ -482,12 +492,8 @@ void GenerateJson( std::ostream & sout,
     {
     std::string line;
     std::getline( iStream, line );
-    size_t quotePosition = line.find( '"' );
-    while( quotePosition != std::string::npos )
-      {
-      line = line.replace( quotePosition, 1, "\\\"" );
-      quotePosition = line.find( '"', quotePosition + 2 );
-      }
+    ReplaceCharacter(line, '\\', "\\\\");
+    ReplaceCharacter(line, '"', "\\\"");
     sout << "\"" << line << "\\n\"\n";
     }
   sout << ";\n";

GenerateCLP/Testing/PointExample1/PointExample1.xml

@@ -41,5 +41,19 @@
       <description>Multi Float</description>
       <label>MultiFloat</label>
     </float>
+    <string>
+      <name>SimpleString</name>
+      <longflag>--string</longflag>
+      <description>Simple string to test that the escaping by Generate CLP</description>
+      <label>Simple String</label>
+      <default>This doublequote " and this quoted "word" should be escaped</default>
+    </string>
+    <string>
+      <name>CDataSimpleString</name>
+      <longflag>--cdataString</longflag>
+      <description>Simple string to test that the escaping by Generate CLP while using CDATA</description>
+      <label>CDATA Simple String</label>
+      <default><![CDATA[This doublequote " and this quoted "word" should be escaped]]></default>
+    </string>
   </parameters>
 </executable>