icon: search by icon's name #131

This will make fnott search for icons by their names in addition to their path name.

Some icon themes use the name of the theme rather than their paths in their inheritance list which resulted in fnott not finding the correct themes to inherit from.

This also makes it possible to specify the theme name in fnott.ini similar to GTK's settings.ini

Missed this part of the spec:

the list of base directories and the internal name of the current theme

I though by "internal" they meant the Name field, but:

The internal name of the theme is the name of the subdirectory

However, some themes use spaces in the Inherits list for example:

Inherits=breeze-dark, hicolor

fnott will try to load a directory named hicolor (with a space in the beginning).
but since internal names can't have spaces, I think the strtok() should treat spaces as delimiters too, thoughts?

I think we can strip spaces, yes.

Technically, these themes are broken; inherits isn't supposed to be a list:

The name of the theme that this theme inherits from.

In addition to that, there's no reason to explicitly include hicolor in inherits, since it's the default fallback.

Anyway, since we already handle lists in inherits, stripping spaces seems like the right thing to do.