build: install eo files per default

in the last release we turned that off, because we started to stabelize
API back there, but the .eo file format wasnt ready yet.

Now, the file format is stable. And we stabelized more widgets, which
means, we should also install the .eo files per default.

Reviewed-by: Stefan Schmidt <stefan@datenfreihafen.org>
Differential Revision: https://phab.enlightenment.org/D10242

meson_options.txt

@@ -361,7 +361,7 @@ option('elementary-base-dir',
 
 option('install-eo-files',
   type: 'boolean',
-  value: false,
+  value: true,
   description : 'Install any eo file'
 )