Bug 1363992 - Remove support for making jemalloc4 the default. r=njn

build/autoconf/jemalloc.m4

build/moz.configure/memory.configure

js/xpconnect/src/XPCJSContext.cpp

js/xpconnect/src/XPCJSRuntime.cpp

memory/build/jemalloc_config.cpp

memory/build/moz.build

memory/build/zone.c

memory/jemalloc/moz.build

memory/moz.build

memory/mozjemalloc/Makefile.in

memory/mozjemalloc/moz.build

memory/replace/logalloc/replay/Replay.cpp

memory/replace/moz.build

toolkit/moz.configure

xpcom/base/nsMemoryReporterManager.cpp