Remove ifdefs depending on the usage of c++11
Avoid polluting the global namespace with typedefs
Remove thread safety solution for the TNormalizedContext

it is of course crucial to have a thread safe ROOT. On the other
hand it may be premature to impose such an ad hoc solution
for this particular problem.
An improved design could maybe avoid the need of a synchronisation
mechanism altoghether in this case.
Relax a bit the 80 cols limit in TMetaUtils

it is indeed not a requirement of ROOT and could have in some
cases geopardised the clarity of the code.