Revised docs, replaced DBus reinitialization, added deps to @echo alert

Changes I've made:

Added a new (Ubuntu centered) README file, removed the "automatic dbus reinitialization" from the Makefile as it caused the installation to fail in some machines/setups I've tried (low RAM, unconventional ACPI settings); So now after the installation is complete the user has to reboot the machine... This is explained in the new README, also added other two dependencies to the prerequisites @echo alert:

 1. **rpm** (as the installation complains about it not being available)
 2. **python-configobj** (found it necessary for tuned to run in my tests)

I've tested the installation and usage with this modified Makefile in **Ubuntu 14.04** (x86, x86_64 and PowerPC) and everything runs ok.

*P.S. It seems that for the CPU Tunnings to work correctly, tools like cpufrequtils indicator-cpufreq and cpufreqd must be removed from the system, but I'm not totally sure about this yet.*