Fix listing applications in “Startup Applications” if an application lacks an icon

If only one application fails to specify an icon in its .desktop file,
pressing the “+” button in “Startup Applications” fails.
If the application at least specifies a name, continue to build
the application list without an icon for that application.

https://bugzilla.gnome.org/show_bug.cgi?id=708900
allow localized searches

The default encoding for python2 is ASCII, a localized
character can't be represented using this encoding.

UTF-8 allow represent every character in the Unicode character set.

**UTF-8 is the default encoding for python3
more info: http://docs.python.org/3.3/howto/unicode.html
be more conservative with unicode errors