Add the concept of implicit rules to (centrally) support automatic translation of
STL collection from numeric type to other numeric type or for when the contained
class has some rules.  Currently enabled only when the target is an std::vector.

Implement the transformation from STL container of numeric to any other numeric
type (both in TGenCollectionStreamer and TStreamerInfo[Actions]).

Migrate more of the conversions to TStreamerInfoActions.

Fix the Conversion of a Double32 or Float16 inside a collection of object to another
type (the previous implemetation was not supporting the customization of the factor
nor the number of bits).

Add TBuffer::ReadFastArrayWithNbits and WithFactor for use in the StreamerInfo Actions.

TStreamerInfoActions:

Introduce WithFactorMarker and NoFactorMarker to allow for less code duplicaton when
supporting Float16_t and Double32_t.
Replace the collection-memberwise action from loop over simple operation to using
ReadFastArray (to be compatible with TBufferXML).


git-svn-id: https://root.cern.ch/svn/root/branches/v5-34-00-patches@48931 27541ba8-7e3a-0410-8455-c3a389f83636