.editorconfig: add .editorconfig file, make tab_size = 4 (#2779)
.editorconfig: add .editorconfig file, make tab_size = 4 (#2779)


ming-relax/tidb,ngaut/tidb,liyu4/tidb,louishust/tidb,spongedu/tidb,coocood/tidb,pingcap/tidb,cosmtrek/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,yuanwhy/tidb,zimulala/tidb,Cofyc/tidb,ming-relax/tidb,pingcap/tidb,pingcap/tidb,qhsong/tidb,tiancaiamao/tidb,ueizhou/tidb,kyle-wang/tidb,silenceper/tidb,gaocegege/tidb,ngaut/tidb,JinheLin/tidb,silenceper/tidb,tiancaiamao/tidb,mccxj/tidb,myrice/tidb,mccxj/tidb,ngaut/tidb,EvilMcJerkface/tidb,yangwenmai/tidb,kyle-wang/tidb,yuanwhy/tidb,c4pt0r/tidb,yangwenmai/tidb,astaxie/tidb,astaxie/tidb,ngaut/tidb,simon-xia/tidb,ngaut/tidb,myrice/tidb,qhsong/tidb,anywhy/tidb,Nify/tidb,qiuyesuifeng/tidb,silentred/tidb,ueizhou/tidb,wusphinx/tidb,8cbx/tidb,Nify/tidb,pingcap/tidb,pingcap/tidb,kyle-wang/tidb,XuHuaiyu/tidb,Cofyc/tidb,wusphinx/tidb,EvilMcJerkface/tidb,XuHuaiyu/tidb,zs634134578/tidb,coocood/tidb,zimulala/tidb,8cbx/tidb,anywhy/tidb,spongedu/tidb,simon-xia/tidb,c4pt0r/tidb,JinheLin/tidb,louishust/tidb,qiuyesuifeng/tidb,zs634134578/tidb,c4pt0r/tidb,cosmtrek/tidb,silentred/tidb,kyle-wang/tidb,kyle-wang/tidb,gaocegege/tidb,CodeRushing/tidb,kyle-wang/tidb,c4pt0r/tidb,liyu4/tidb,CodeRushing/tidb,pingcap/tidb