@unchecked is better than matching on _ in this case, because we want to
fail on an unexpected case, rather than silently proceed.

Gsdt - Fixup to Chisel connections and direction - PR 200 revisited.

Add Data dir method to Chisel compatibility layer.

Massive rename of CompileOptions.

Massage CompileOption names in an attempt to preserve default (Strict) CompileOptions in the absence of explicit imports.
NOTE: Since the default is now strict, we may encounter errors when we generate connections for clients (i.e., in Vec.do_apply() when we wire up a sequence).
We should really thread the CompileOptions through the macro system so the client's implicits are used.

Don't use firrtlDirection for direction checks - fix #298.

firrtlDirection should only be used for emitting firrtl. Any checks on the actual direction should use the bound Direction `dir`.

Add Strict default for compile options, onto gsdt

Scaladocs for utils

Additionally, fix Clock.asUInt (previously, it threw an esoteric exception), and add a simple test of both.

In the Chisel frontend, the implicit clock is named clock, but in the
generated FIRRTL, it is named clk.  There is no reason for this
discrepancy, and yet fixing it is painful, as it will break test harnesses.
Better to take the pain now than later.

Resolves #258.

o explain why this merge is necessary,

This reverts commit 920f6dc1.

Add IrrevocableIO subclass of DecoupledIO that promises not to change .bits on a cycle after .valid is high and .ready is low

Fix bug in Printable FullName of submodule port

Printable was using HasId.instanceName to get full names of Chisel nodes.
instanceName uses the parent module of the HasId to get the Component to use in
calling fullName on the underlying Ref. Unfortunately this means that any
reference to a port of a instance will leave off the instance name. Fixing this
required the following:

- Add Component argument to Printable.unpack so that we can call Arg.fullName
  directly in the Printable
- Pass the currently emitting module as the Component to Printable.unpack in
  the Emitter
- Remove ability to create FullName Printables from Modules since the Module
  name is not known until after the printf is already emitted

This commit also updates the PrintableSpec test to check that FullName and
Decimal printing work on ports of instances

Printable is a new type that changes how printing of Chisel types is represented
It uses an ordered collection rather than a format string and specifiers
Features:
 - Custom String Interpolator for Scala-like printf
 - String-like manipulation of "hardware strings" for custom pretty-printing
 - Default pretty-printing for Chisel data types