Log Message:
editors/featherpad: update to 0.18.0

-Fixed an old but rare problem in highlighting of multiline comments.
-Added Pascal syntax highlighting.
-Added Java syntax highlighting.
-Better highlighting of numeric literals in some programming languages.
-Taken into account some general variables of Perl when highlighting its syntax.
-Taken into account the possibility of using unpaired or different paired
delimiters for the second part of Perl's replacement operators.
-Fixes and improvements to Ruby syntax highlighting.
-Prevent Qt from giving any non-plain text to the selection clipboard.
-Made PageUp/PageDown select the first/last item of the search history when the
search line-edit is focused.
-Fixed the lack of Perl-style comments in PHP syntax highlighting.
-If needed, save cursor positions when the app is terminated by SIGTERM.
-Prevent the spell checker from changing an uneditable document.
-Added an icon to the tabs/view-items of files that have targets but aren't
symlinks (e.g., their parent directories are symlinks). Also, (1) when a final
target exists, two items are added to the tab/view-item context menu for
copying its path and opening it, and (2) if a file and some of its targets are
opened, only the first one is editable by default.
-Added JSON syntax highlighting.
-Added "math" and "equation" to LaTex syntax highlighting.