google: "gnome 2.8 mime type"
MIME type-based app integration in GNOME2	
	https://www.programmersought.com/article/6185101594/
HOWTO Mime Times and File Assoc with FC3 Gnome 2.8	
	https://forums.fedoraforum.org/showthread.php?26875-How-To-Mime-Types-and-file-associations-with-FC3-Gnome-2-8
Custom MIME for individual users
	https://help.gnome.org/admin/system-admin-guide/stable/mime-types-custom-user.html.en
Unified system
	https://specifications.freedesktop.org/shared-mime-info-spec/latest/ar01s02.html#idm45642550600720
shared MIME-info database
	https://specifications.freedesktop.org/shared-mime-info-spec/latest/

~~~~~~~
based on https://help.gnome.org/admin/system-admin-guide/stable/mime-types-custom-user.html.en
	~/.local/share/mime/packages/application-x-pryrt.html		(2018-Jul-28)
	+++
		<?xml version="1.0" encoding="UTF-8"?>
		<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
		  <mime-type type="application/x-ltxenvision">
		    <comment>LTX-MX EnVision Source File</comment>
		    <glob pattern="*.evo"/>
		    <glob pattern="*.eva"/>
		  </mime-type>
		  <mime-type type="application/x-ltxcadence">
		    <comment>LTX-MX Cadence Source File</comment>
		    <glob pattern="*.tp"/>
		    <glob pattern="*.tmod"/>
		    <glob pattern="*.mod"/>
		  </mime-type>
		  <mime-type type="application/x-stdf">
		    <comment>STDF datalog</comment>
		    <glob pattern="*.std"/>
		    <glob pattern="*.stdf"/>
		    <glob pattern="*.std_open"/>
		  </mime-type>
		</mime-info>
	===
	~/.local/share/applications/defaults.list 			(2018-Jul-27)
		[Default Applications]
		application/x-stdf=stdf.desktop
		application/x-ltxcadence=cadence.desktop
		application/x-ltxenvision=envision.desktop
	~/.local/share/applications/cadence.desktop			(2018-Jul-28)
		[Desktop Entry]
		Encoding=UTF-8
		Name=Edit Cadence Source File
		MimeType=application/x-ltxcadence
		Exec=/usr/X11R6/bin/gvim %f
		Type=Application
		Icon=icon-character-map.png
		Terminal=false
		NoDisplay=true
	`update-mime-database ~/.local/share/mime`
	`update-desktop-database ~/.local/share/applications`