Fix Coverity reports

TDatabasePDG.cxx: #11418 getc returns an int
TTree.cxx: #10577 unused variable
TTreeFormula.cxx: #10795,#10796,#13272,#13273,#13274,#14173 strcat -> strncat, strcpy -> strncpy
TTreePlayer.cxx: #10891,#10892,#14169,#14170,#14172 strcpy -> strncpy
TStreamerElement.cxx: #12537,#13200,#13318,#13586,#13587,#13588,#13589,#13590,#13591,#13596,#13597,#13598 strcpy,sprintf -> strncpy,snprintf (or TString)
TStreamerInfo.cxx: #13470,#13787,#13788 strcpy,sprintf -> strncpy,snprintf (or TString)
TBranchProxy.cxx: null pointer dereference.
TBranch.cxx: #10689 null pointer dereference.
loadfile.cxx: #10767,#12387.#12388,#12389,#12521,#12522,#13514,etc.. strcpy,sprintf -> strncpy,snprintf  (or TString)
TFileDrawMap.cxx: #10893,#10894,#10895,#13460,#14176,#14177,#14718,#14179 strcpy,sprintf -> strncpy,snprintf  (or TString)
TFile.cxx: #13789,#13193,#13450 strcpy,sprintf -> strncpy,snprintf  (or TString)
TMethod.cxx: #10802,#13310 strcpy,sprintf -> strncpy,snprintf  (or TString)
TClass.cxx: #10814,#13122,#13467,#13468,#13490 strcpy,sprintf -> strncpy,snprintf  (or TString)
TDataMember.cxx: #10825,#13241,#13329,#13330,#13584 strcpy,sprintf -> strncpy,snprintf  (or TString)
TFormula.cxx: #13263,#13783 sprintf -> snprintf or TString
stlLoader.cxx: #13599 static array -> G__FastAllocString


git-svn-id: http://root.cern.ch/svn/root/trunk@35450 27541ba8-7e3a-0410-8455-c3a389f83636