[install-guide/f21-branch] Updated boot options with changes in f21

[pbokoc]

commit 24b8e923ec8ef025f687ffd7fac9cf0eb4e51c50
Author: Petr Bokoc <pbokoc at redhat.com>
Date:   Tue Jan 27 18:20:47 2015 +0100

    Updated boot options with changes in f21

 en-US/Boot_Options.xml |   18 +++++++++++++++++-
 1 files changed, 17 insertions(+), 1 deletions(-)
---
diff --git a/en-US/Boot_Options.xml b/en-US/Boot_Options.xml
index e727801..9f2f672 100644
--- a/en-US/Boot_Options.xml
+++ b/en-US/Boot_Options.xml
@@ -179,7 +179,7 @@
                                 <para>
                                     File system UUID, for example <systemitem>UUID=8176c7bf-04ff-403a-a832-9557f94e61db</systemitem>
                                 </para>
-                            </listitem>
+                            </listitem>emo
                         </itemizedlist>
                         <para>
                             Non-alphanumeric characters must be represented as <literal>\x<replaceable>NN</replaceable></literal>, where <replaceable>NN</replaceable> is the hexadecimal representation of the character. For example, <literal>\x20</literal> is a white space ("<literal> </literal>").
@@ -782,6 +782,22 @@
                         </para>
                     </listitem>
                 </varlistentry>
+                <varlistentry>
+                    <term><option>inst.memcheck</option></term>
+                    <listitem>
+						<para>
+							Perform a check at the beginning of the installation to determine if there is enough available RAM. If there is not enough memory detected, the installation will stop with an error message. This option is enabled by default; use <option>inst.memcheck=0</option> to disable it. 
+						</para>
+                    </listitem>
+                </varlistentry>
+                <varlistentry>
+                    <term><option>inst.dnf</option></term>
+                    <listitem>
+						<para>
+							Use the new <application>DNF</application> backend for package installation and dependency resolution instead of <application>Yum</application>. See <ulink url="https://fedoraproject.org/wiki/Features/DNF">the DNF feature page</ulink> on the Fedora Wiki for information about <application>DNF</application>.
+						</para>
+                    </listitem>
+                </varlistentry>
             </variablelist>
         </section>