Show context menu for folders in FmDirTreeView sidebar.

It is implemented as simple version of standard FmFileMenu with
elements such as Copy/Cut/Del removed from the menu.
[#3598836]Place columns of Compact View in right-to-left order for RTL locales.
New APIs fm_hide_file() and fm_unhide_file()

New APIs just send a job to change "hidden" file attribute.
Add "hidden" attribute support info file properties dialog.

The new support adds a check button on bottom of "Permissions" tab.
The button is unchangeable if file doesn't support the change.
Tooltips are updated accordingly.
Correct "hidden" attribute for native desktop entry files.

It was set if file is dot-file but for desktop entries the "Hidden" key
should be checked as well.
Item 'Hide'/'Unhide' in MoveCategory of FmFileMenu if FS supports it.

If file system can change file attribute "hidden" then it is reasonable
to have the element in the file context menu as well.