documentation update

Author: ddmitov

doc/perl-scripts-api.md

@@ -61,7 +61,7 @@ A JavaScript configuration object for a Perl script run by PEB must have the fol
   };
   ```
 
-A JavaScript configuration object for a Perl script run by PEB may also have the following additional properties:
+A JavaScript configuration object for a Perl script run by PEB may also have the following optional properties:
 
 * **perlInterpreter**  
   ``String`` for the relative path of a [relocatable](https://github.com/skaji/relocatable-perl) Perl interpreter used by PEB  
@@ -86,4 +86,4 @@ A JavaScript configuration object for a Perl script run by PEB may also have the
   The actual creation of a new file is performed by the Perl script and not by PEB.  
 
   * ``{"directory":"Your Dialog Title"}``  
-  When ``directory`` type of dialog is used, an existing directory may be selected or a new directory may be created and then selected; any new directory will be immediately created by PEB.
+  When ``directory`` type of dialog is used, an existing directory may be selected or a new directory may be created and then selected. Any new directory will be immediately created by PEB.