Starting f24 and later, the gsettings schema compilation is
automatically triggered when needed, but we need to explicitly do
it for earlier versions [0].

This patch also disables the gsettings schema local compilation so
that this is not done during 'make install' since the schema will
be compiled post install and it is also not needed locally.

[0] - https://fedoraproject.org/wiki/Packaging:Scriptlets?rd=Packaging:ScriptletSnippets#GSettings_Schema

Change-Id: I8b78c4d50e2208c29200f89d3947aa3117fbb6ab
Tuleap: #975