Add basic document for microshift preset

Author: praveenkumar

docs/source/meta/product-attributes.adoc

@@ -21,6 +21,7 @@
 :openshift: OpenShift
 :ocp: {openshift} Container Platform
 :okd: OKD
+:ushift: MicroShift
 
 // Product naming
 :prod: CRC

docs/source/topics/con_about-presets.adoc

@@ -3,7 +3,7 @@
 
 [role="_abstract"]
 {prod} presets represent a managed container runtime and the lower bounds of system resources required by the instance to run it.
-{prod} offers presets for {ocp}, {okd} and the Podman container runtime.
+{prod} offers presets for {ocp}, {okd}, {ushift} and the Podman container runtime.
 
 On {msw} and {mac}, the {prod} guided installer prompts you for your desired preset.
 On Linux, the {ocp} preset is selected by default.

docs/source/topics/ref_minimum-system-requirements.adoc

@@ -20,9 +20,15 @@ Depending on the desired container runtime, {prod} requires the following system
 * 9 GB of free memory
 * 35 GB of storage space
 
+=== For {ushift}
+
+* 2 physical CPU cores
+* 4 GB of free memory
+* 35 GB of storage space
+
 [NOTE]
 ====
-The {ocp} cluster requires these minimum resources to run in the {prod} instance.
+The {ocp} and {ushift} presets require these minimum resources to run in the {prod} instance.
 Some workloads may require more resources.
 To assign more resources to the {prod} instance, see link:{crc-gsg-url}#configuring-the-instance_gsg[Configuring the instance].
 ====