Revert change to FONTCONFIG_FILE, so we have a complete fontconfig configuration (#144)
Revert change to FONTCONFIG_FILE, so we have a complete fontconfig configuration (#144)

* Revert "Fix FONTCONFIG_PATH to match where we generate fonts.conf (#115)"

This reverts commit f07d125e3ba4d1175ab8f4615e453a933e2fffa7.

The fonts.conf generated by desktop-launch is not a complete fontconfig
configuration, but instead intended to be included by the main
fonts.conf file.  Among other things, this change stops fontconfig from
looking for cache files in /var/cache/fontconfig, which in turn forces
applications to regenerate those caches on first run.

* Add a comment describing how the fontconfig fragment is integrated into
the full fontconfig configuration.

ubuntu/snapcraft-desktop-helpers