delete superfluous horizontal line plus preceding empty lines at the end of doc files

doc/src/Howto_diffusion.rst

@@ -21,6 +21,3 @@ diffusion coefficient.  The instantaneous VACF values can be
 accumulated in a vector via the :doc:`fix vector <fix_vector>` command,
 and time integrated via the :doc:`variable trap <variable>` function,
 and thus extract D.
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-
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doc/src/dump_adios.rst

@@ -85,6 +85,3 @@ Related commands
 """"""""""""""""
 
 :doc:`dump <dump>`, :doc:`dump_modify <dump_modify>`, :doc:`undump <undump>`
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-
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doc/src/fix_eos_table_rx.rst

@@ -221,6 +221,3 @@ Related commands
 :doc:`pair dpd/fdt <pair_dpd_fdt>`
 
 **Default:** none
-
-
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doc/src/fix_oneway.rst

@@ -62,6 +62,3 @@ Related commands
 :doc:`fix wall/reflect <fix_wall_reflect>` command
 
 **Default:** none
-
-
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doc/src/improper_inversion_harmonic.rst

@@ -71,6 +71,3 @@ Related commands
 :doc:`improper_coeff <improper_coeff>`
 
 **Default:** none
-
-
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doc/src/pair_smd_hertz.rst

@@ -62,6 +62,3 @@ Related commands
 :doc:`pair_coeff <pair_coeff>`
 
 **Default:** none
-
-
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doc/src/pair_smd_tlsph.rst

@@ -78,6 +78,3 @@ Related commands
 :doc:`pair_coeff <pair_coeff>`
 
 **Default:** none
-
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doc/src/pair_smd_triangulated_surface.rst

@@ -63,6 +63,3 @@ Related commands
 :doc:`pair_coeff <pair_coeff>`
 
 **Default:** none
-
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doc/src/pair_smd_ulsph.rst

@@ -93,6 +93,3 @@ Related commands
 :doc:`pair_coeff <pair_coeff>`
 
 **Default:** none
-
-
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