Merge branch...

Merge branch '62-psdumpframe-option-only-works-for-opal-cycl-but-this-is-not-specified-in-the-manual' into 'master'

Resolve "`PSDUMPFRAME` option only works for OPAL-cycl, but this is not specified in the manual"

Closes #62

See merge request OPAL/documentation/manual!132

control.asciidoc

@@ -121,6 +121,8 @@ PSDUMPFRAME::
   * `GLOBAL`: data is written in the global Cartesian frame;
   * `BUNCH_MEAN`: data is written in the bunch mean frame or;
   * `REFERENCE`: data is written in the frame of the reference particle.
+  Currently only available for _OPAL-cycl_. In _OPAL-t_ the phase-space
+  is always written in the frame of the reference particle.
 SPTDUMPFREQ::
   Defines after how many time steps we dump the phase space of single
   particle. It is always useful to record the trajectory of reference