Update gotchas.rst with discussion of issue 2388
Update gotchas.rst with discussion of issue 2388

Just a small update to the gotchas page to reference a potential
gotcha using the reindex_like functionality.

jorisvandenbossche/pandas,DGrady/pandas,zfrenchee/pandas,GuessWhoSamFoo/pandas,kdebrab/pandas,rs2/pandas,nmartensen/pandas,kdebrab/pandas,cbertinato/pandas,gfyoung/pandas,harisbal/pandas,datapythonista/pandas,TomAugspurger/pandas,MJuddBooth/pandas,dsm054/pandas,dsm054/pandas,louispotok/pandas,jmmease/pandas,gfyoung/pandas,louispotok/pandas,cython-testbed/pandas,louispotok/pandas,nmartensen/pandas,linebp/pandas,gfyoung/pandas,jreback/pandas,pandas-dev/pandas,jmmease/pandas,GuessWhoSamFoo/pandas,dsm054/pandas,nmartensen/pandas,jreback/pandas,jreback/pandas,DGrady/pandas,datapythonista/pandas,winklerand/pandas,DGrady/pandas,winklerand/pandas,linebp/pandas,nmartensen/pandas,toobaz/pandas,harisbal/pandas,GuessWhoSamFoo/pandas,winklerand/pandas,jorisvandenbossche/pandas,pratapvardhan/pandas,pandas-dev/pandas,louispotok/pandas,cython-testbed/pandas,amolkahat/pandas,linebp/pandas,rs2/pandas,linebp/pandas,gfyoung/pandas,pratapvardhan/pandas,linebp/pandas,kdebrab/pandas,toobaz/pandas,toobaz/pandas,kdebrab/pandas,Winand/pandas,zfrenchee/pandas,TomAugspurger/pandas,TomAugspurger/pandas,pratapvardhan/pandas,amolkahat/pandas,jmmease/pandas,jreback/pandas,pratapvardhan/pandas,Winand/pandas,Winand/pandas,datapythonista/pandas,toobaz/pandas,pandas-dev/pandas,dsm054/pandas,cython-testbed/pandas,harisbal/pandas,DGrady/pandas,Winand/pandas,gfyoung/pandas,amolkahat/pandas,cbertinato/pandas,MJuddBooth/pandas,cython-testbed/pandas,jmmease/pandas,toobaz/pandas,kdebrab/pandas,pratapvardhan/pandas,MJuddBooth/pandas,winklerand/pandas,Winand/pandas,harisbal/pandas,cbertinato/pandas,jorisvandenbossche/pandas,DGrady/pandas,zfrenchee/pandas,linebp/pandas,jmmease/pandas,TomAugspurger/pandas,rs2/pandas,MJuddBooth/pandas,jmmease/pandas,winklerand/pandas,rs2/pandas,jorisvandenbossche/pandas,zfrenchee/pandas,GuessWhoSamFoo/pandas,harisbal/pandas,winklerand/pandas,louispotok/pandas,zfrenchee/pandas,amolkahat/pandas,Winand/pandas,jreback/pandas,cython-testbed/pandas,pandas-dev/pandas,amolkahat/pandas,MJuddBooth/pandas,nmartensen/pandas,GuessWhoSamFoo/pandas,nmartensen/pandas,DGrady/pandas,cbertinato/pandas,dsm054/pandas,cbertinato/pandas,datapythonista/pandas