Update Release Notes for v6.1.0

diff --git a/SALOME_5_1_2_Release_Notes.pdf b/SALOME_5_1_2_Release_Notes.pdf
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diff --git a/SALOME_6_1_0_Release_Notes.pdf b/SALOME_6_1_0_Release_Notes.pdf
new file mode 100755 (executable)
index 0000000..9a99cf3
Binary files /dev/null and b/SALOME_6_1_0_Release_Notes.pdf differ