Preliminary inclusion of uixx objects properties in the manual (bug #46076) * doc/interpreter/genpropdoc.m: add uixx objects to the list of supported graphics objects * doc/interpreter/genpropdoc.m (get_doc): add uixx objects and their specific properties (currently empty documentation) * doc/interpreter/plot.txi("Interacting with Plots"): add a note and a reference about ui* family of functions. * doc/interpreter/plot.txi("Interacting with Plots"): for consistency, remove "uimenu" reference. All the other uixx are already in the gui section * doc/interpreter/plot.txi("graphics data structure"): add uixx objects * doc/interpreter/gui.txi("UI Elements"): add "uimenu" function reference * doc/module.mk: add rules to build uixx properties texi files. * graphics.in.h: make uixx "__object__" property (Octave internal) hidden so that it does not appear in the documentation.

bug_36025_TEST_FILES = \
  test/bug-36025/@testclass/one.m \
  test/bug-36025/@testclass/testclass.m \
  test/bug-36025/@testclass/two.m \
  test/bug-36025/bug-36025.tst

TEST_FILES += $(bug_36025_TEST_FILES)