remove rogue slash in citation

Author: bobleesj

README.rst

@@ -65,7 +65,7 @@ Citation
 
 If you use diffpy.pdffit2 in a scientific publication, we would like you to cite the following paper:
 
-        C\. L. Farrow, P. Juhás, J. W. Liu, D. Bryndin, E. S. Božin, J. Bloch, Th. Proffen
+        C. L. Farrow, P. Juhás, J. W. Liu, D. Bryndin, E. S. Božin, J. Bloch, Th. Proffen
         and S. J. L. Billinge, PDFfit2 and PDFgui: computer programs for studying nanostructure
         in crystals (https://stacks.iop.org/0953-8984/19/335219), *J. Phys.: Condens. Matter*, 19, 335219 (2007)