Add bToF view

compact/subsystem_views/tof_only.xml

+<lccdd xmlns:compact="http://www.lcsim.org/schemas/compact/1.0"
+       xmlns:xs="http://www.w3.org/2001/XMLSchema"
+       xs:noNamespaceSchemaLocation="http://www.lcsim.org/schemas/compact/1.0/compact.xsd">
+
+       <debug>
+         <type name="surface"       value="0"/>
+         <type name="material"      value="0"/>
+         <type name="readout"       value="0"/>
+         <type name="segmentation"  value="0"/>
+         <type name="limits"        value="0"/>
+         <type name="region"        value="0"/>
+         <type name="includes"      value="0"/>
+       </debug>
+
+  <documentation level="-1">
+  # Athena Detector 
+  - https://eicweb.phy.anl.gov/EIC/detectors/athena.git 
+  - https://eicweb.phy.anl.gov/EIC/detectors/ip6.git
+  </documentation>
+
+  <!-- Some information about detector  -->
+  <info name="Athena Detector" title="Athena Detector"
+        author="Athena Collaboration"
+	url="https://eicweb.phy.anl.gov/EIC/detectors/athena.git"
+	status="development"
+	version="v1 2021-03-16">
+  <comment> Athena </comment>
+  </info>
+  <define>
+  <documentation level="2">
+      ## Main Constant Definitions
+
+      The ip6 (or other ip) defines should be included first.
+      These files have only a define tags.
+  </documentation>
+    <include ref="ip6/ip6_defs.xml" /> 
+    <include ref="ip6/far_forward_fields_275.xml" />
+    <include ref="compact/definitions.xml" />
+  </define>
+
+  <includes>
+    <gdmlFile ref="compact/elements.xml"/>
+    <gdmlFile ref="compact/materials.xml"/>
+    <file     ref="compact/optical_materials.xml"/>
+  </includes>
+
+  <limits>
+    <limitset name="EICBeamlineLimits">
+      <limit name="step_length_max" particles="*" value="1.0" unit="mm" />
+      <limit name="track_length_max" particles="*" value="1.0" unit="mm" />
+      <limit name="time_max" particles="*" value="0.1" unit="ns" />
+      <limit name="ekin_min" particles="*" value="0.001" unit="MeV" />
+      <limit name="range_min" particles="*" value="0.1" unit="mm" />
+    </limitset>
+    <limitset name="cal_limits">
+      <limit name="step_length_max" particles="*" value="5.0" unit="mm"/>
+    </limitset>
+  </limits>
+
+  <display>
+  <include ref="compact/colors.xml" />
+  <include ref="compact/display_detailed.xml" />
+  </display>
+
+  <documentation level="10">
+    ## eRICH only
+  </documentation>
+  <include ref="ip6/beampipe.xml" />
+  <include ref="compact/tof_barrel.xml" />
+
+</lccdd>