sourceMap support (wip)

added concat.coffee - manage compiled sources concat. produce map

source_file handle new compiler result : {compiled, map}

source_file keep copy of compiled source and have 'sourceMap' property
commonJs wrapper correctly setup input map, removed concat.coffee, (in generate)
Update loggy version.
Fix code style.
Remove removed files from compiled output. Closes gh-558.
Update btw.
Add logging.
Add source maps support.
Refactor source maps code.
Merge branch 'refs/heads/master' into topics/source-maps

Conflicts:
	package.json
FUCKING SOURCE MAPS YES
fix source maps for non-commonjs configurations

this method allows custom wrapper functions to work the same way as before (i.e. without special source node handling)
Merge pull request #562 from es128/fix-sourcemaps

fix source maps for non-commonjs configurations
Add adequate errors for npm install req.
Merge branch 'master' of github.com:brunch/brunch
Fix typo.
keeping track of what files are compiling so that things aren't recompiled fifty bajillion times
fix sourcemaps for custom module definition
Merge pull request #566 from es128/fix-sourcemaps

fix sourcemaps for custom module definition
Merge pull request #563 from bolster/multiple-compile-fix

Multiple Recompilation