Update README.rst

 *  The `./configure` line telling you to pass `--sysconfdir` contained a typo.
 *  The `gconftool-2` line to install the `guake.schemas` did not work, because `--makefile-install-rule` expects you to set the `GCONF_CONFIG_SOURCE`. The man page says:

    > Properly  installs  schema  files  on  the command line into the database. GCONF_CONFIG_SOURCE environment variable should be set to a non-default config source or set to the empty string to use the default.