Implement much expanded dumper support. We now print stuff like:

<MODULE_BLOCK NumWords=27 BlockCodeSize=3>
  <TYPE_BLOCK NumWords=7 BlockCodeSize=4>
    <NUMENTRY op0=7>
    <POINTER op0=1>
    <FUNCTION op0=0 op1=2 op2=2 op3=2 op4=2>
    <VECTOR op0=2 op1=3>
    <INTEGER op0=64>
    <VECTOR op0=8 op1=5>
    <INTEGER op0=16>
    <VOID>
...

With work, the operands can be pretty printed symbolically.

llvm-svn: 36579