Logger 1 (#338)

* Create a simple system for executions and command line parameters
New model for tracking parameters and having those parameters
register scopt command to allow the parameters to be set by
command line args.
Create composable forms of the these parameters to allow separate
elements of the chisel3 toolchain to combine these parameters
Create execution return structures that simplify return values
to earlier toolchain elements

* just a little bit of cleanup

* Fixes for Adam's comments on PR

* knuckled under to self-pressure to allow former -i and -o to work

* knuckled under to self-pressure to allow former -i and -o to work

* show defaults for command line args with them

* A couple of fixes from merging latest master

* Implement a log4scala like logging system
This system has the rather remarkable property
that it is possible to turn it on conveniently when
you want it.  It also provides for class level granularity
as well as the traditional Error, Warn, Info, Debug

* some style fixes and change infoMode default to append per PR #328

* some style fixes and change infoMode default to append per PR #328

* support -i -o and -X
a couple of indentation and spacing fixes