ENYO-3672: fix bug to substitute file contents using substit.vars

ENYO-3672: fix to use both of substit.json and substitu.vars together

Enyo-DCO-1.1-Signed-off-by Junil Kim <logyourself@gmail.com>
ENYO-3672: _applyRegexpSubstitutions for replacing contents via regexp

ENYO-3672: revert _applyVarsSubstitutions

Enyo-DCO-1.1-Signed-off-by Junil Kim <logyourself@gmail.com>
ENYO-3672: changed log string

Enyo-DCO-1.1-Signed-off-by Junil Kim <logyourself@gmail.com>
bump version to 0.3.4 from 0.2.4
Merge pull request #13 from enyojs/ENYO-3672

ENYO-3672: fix bugs regarding substitution