Add utility functions & tests
Move majority of FSv1 to core.py
Add recipe

This new module in freesurfer.v1 add a function
for generating a script and tcl scripts to execute
an opinionated pipeline for freesurfer.

The recipe is available at the commandline through
'build-recon-v1'
Make xvfb e files end with .err
Reconfigure tools page for explicitness

* Also add bit about functions v recipes
* Tweak conf.py to autodoc current code
* Tweak Makefile to clean docs before building
Add build_recipe documentation

* build_recipe returns paths to written scripts
* main script is made executable
* binary prints path to main script
improve arg parsing for build-recon-v1

* no more escaping args
* add epilog re: recon-all flags
Add util tests
Add cov & install Make commands

* update README
Merge pull request #6 from VUIIS/recon-script

Add recipe layer to freesurfer module

Closes #5.