builder: fix conflicts on files
builder: fix conflicts on files

The new defined getter files is conflict with the old files which is
used for counting the rendered files. That doesn't work with Node
v0.12.x.

This fixes #24 and thanks to @nantas's issue report :)
R=@nantas

fireball-x/firedoc,fireball-x/firedoc,fireball-x/firedoc