Change TableInputFormatBase to take interface arguments

As part of the ongoing interface abstraction work, I'm now investigating TableInputFormatBase, which has two methods that break encapsulation:

protected HTable getHTable();
protected void setHTable(HTable table);

While these are protected methods, the base @InterfaceAudience.Public is abstract, meaning that it supports extension by user code.

I propose deprecating these two methods and replacing them with these four, once the Table interface is merged:

protected Table getTable();
protected void setTable(Table table);
protected RegionLocator getRegionLocator();
protected void setRegionLocator(RegionLocator regionLocator);

Since users will frequently call setTable and setRegionLocator together, it probably also makes sense to add the following convenience method:

protected void setTableAndRegionLocator(Table table, RegionLocator regionLocator);