Reviews NativeCall

Eliminates accidental MD refs #2022

Also reviews changes in #1376 have been made. "is native" is
added. Still the page needs improvement, but this closes #1376

doc/Language/nativecall.pod6

@@ -87,11 +87,11 @@ X<|int8>X<|int16>X<|int32>X<|int64>X<|uint8>X<|uint16>X<|uint32>X<|uint64>X<|lon
     ssize_t        (ssize_t in C)
 =end table
 
-Don't use Perl 6 native types like C<int> or C<num>, as they don't have to
+Don't use Perl 6 native types like C<int> or C<num> in native calls, as they don't have to
 correspond to the local C equivalent (e.g., Perl 6's C<int> can be 8 bytes but
 C's C<int> is only 4 bytes).
 
-Note that the lack of a C<returns> trait is used to indicate void return type.
+Note that the lack of a C<returns> trait is used to indicate C<void> return type.
 Do I<not> use the 'void' type anywhere except in the Pointer parameterization.
 
 For strings, there is an additional "encoded" trait to give some extra hints on
@@ -131,7 +131,7 @@ call, the argument must be manually encoded and passed as C<CArray[uint8]>:
 X<|repr>X<|is repr>X<|CStruct (native representation)>
 =head1 Specifying the native representation
 
-When working with native functions, sometimes you need to specify what kind of native data structure is going to be used. `is repr` is the term employed for that.
+When working with native functions, sometimes you need to specify what kind of native data structure is going to be used. C<is repr> is the term employed for that.
 
 =begin code
 use NativeCall;