Major refactoring of all datapath classes.

There is now a new class called BaseNode that stores all attributes about an
execution node, which replaces the 10+ separate vectors and maps we had
originally. All references to the old vectors and data structures have been
removed.

opcode_func.cpp has been moved into the BaseNode class, so that the
is_<type>_op functions are now more like "attributes" of the node.

All of the init<Property> functions are now called just once, and their values
are stored into the new BaseNode structure.

One characteristic of the refactored code is that whenever possible, I have
replaced iterating by node_ids by iterating over the nodes themselves. Nodes
can now be directly compared to one another, and accessing properties like the
vertices is just a memory operation.

This refactoring passes all unit tests (and thank god we had those or this
would have been impossible to debug), but this commit only handles the common
datapaths and not the gem5 datapaths yet, so gem5 will not compile yet.

TESTED=unit

Change-Id: I7ab3faee25836fa0a2980627cd49600464895fd4

.clang-format

@@ -11,7 +11,7 @@ AlwaysBreakTemplateDeclarations: false
 AlwaysBreakBeforeMultilineStrings: false
 BreakBeforeBinaryOperators: false
 BreakBeforeTernaryOperators: true
-BreakConstructorInitializersBeforeComma: true
+BreakConstructorInitializersBeforeComma: false
 BinPackParameters: false
 ColumnLimit:     80
 ConstructorInitializerAllOnOneLineOrOnePerLine: false
@@ -26,7 +26,7 @@ PenaltyBreakComment: 1000
 PenaltyBreakString: 1000
 PenaltyBreakFirstLessLess: 120
 PenaltyExcessCharacter: 1000000
-PenaltyReturnTypeOnItsOwnLine: 60
+PenaltyReturnTypeOnItsOwnLine: 10000
 PointerBindsToType: true
 SpacesBeforeTrailingComments: 2
 Cpp11BracedListStyle: false