isobmff: make skipping mdat copy the default

Tested:

default case:
```
$ valgrind --tool=massif --detailed-freq=1 ./tools/isobmff in.mp4
$ grep mem_heap_B massif.out.default | awk -F= '{if($2 > max) max=$2} END{print max}'
691167
```

donotskipmdat:

Added the following patch
```
diff --git a/tools/main.cpp b/tools/main.cpp
index def1861..5552cb7 100644
--- a/tools/main.cpp
+++ b/tools/main.cpp
@@ -223,6 +223,7 @@ int main( int argc, char *const * argv )

         try
         {
+            parser.AddOption( ISOBMFF::Parser::Options::DoNotSkipMDATData );
             parser.Parse( path );
         }
         catch( const std::runtime_error & e )
```

And then:
```
$ valgrind --tool=massif --detailed-freq=1 ./tools/isobmff in.mp4
$ grep mem_heap_B massif.out.donotskipmdat | awk -F= '{if($2 > max) max=$2} END{print max}'
682524151
```

Author: chemag

include/Parser.hpp

@@ -68,11 +68,11 @@ namespace ISOBMFF
             /*!
              * @enum        Options
              * @abstract    Parser options.
-             * @constant    SkipMDATData    Do not keep data found in MDAT boxes.
+             * @constant    DoNotSkipMDATData Keep data found in MDAT boxes.
              */
             enum class Options: uint64_t
             {
-                SkipMDATData = 1 << 0
+                DoNotSkipMDATData = 1 << 0
             };
 
             /*!

src/ContainerBox.cpp

@@ -111,7 +111,7 @@ namespace ISOBMFF
                 if
                 (
                        length > ( std::numeric_limits< size_t >::max )()
-                    || ( name == "mdat" && parser.HasOption( Parser::Options::SkipMDATData ) )
+                    || ( name == "mdat" && !parser.HasOption( Parser::Options::DoNotSkipMDATData ) )
                 )
                 {
                     stream.Seek( length - 16, BinaryStream::SeekDirection::Current );
@@ -123,7 +123,7 @@ namespace ISOBMFF
             }
             else
             {
-                if( name == "mdat" && parser.HasOption( Parser::Options::SkipMDATData ) )
+                if( name == "mdat" && !parser.HasOption( Parser::Options::DoNotSkipMDATData ) )
                 {
                     stream.Seek( length - 8, BinaryStream::SeekDirection::Current );
                 }

tools/main.cpp

@@ -223,7 +223,6 @@ int main( int argc, char *const * argv )
 
         try
         {
-            parser.AddOption( ISOBMFF::Parser::Options::SkipMDATData );
             parser.Parse( path );
         }
         catch( const std::runtime_error & e )