checking for GTK3... no
GTK 3 >= 3.0.1 not found
Missing dependencies.
Taking a look to README.packages we can see that some devel packages are
needed for Fedora and OpenSuse with GTK3. Please test in Ubuntu if these
are the missing dependencies, and I will update the file.
sudo apt-get install gtk3-devel gtksourceview3-devel
or
sudo apt-get install libgtksourceview3.0-dev
I've forgotten that now configure sets GTK3 by default, sorry about that.
Hélio