A first step towards theme debugging

issue #2204
- allow handlebars log helper to output to console in dev mode
Fix package.json scripts to be more in line with
expected behavior of npm packages

fixes #1053

- updates travis config to be more in line with
 current dev steps

- fix `grunt-cli` warning from appearing when
 running grunt
Improvements for models

#closes #1655
- removed models as parameter for bookshelf-session
- changed to read permittedAttributes from schema.js
- changed updateTags to be executed at saved event
- added validate to execute after saving event
- added test for published_at = null (see #2015)
- fixed typo in general.hbs
Merge pull request #2169 from sebgie/issue#1655

Improvements for models
Show parse error message during a failed import

adds support for outputting error message during a failed JSON.parse
This will help people identify the problem with their JSON source
and hopefully be able to aid them in resolving said issue.
Merge pull request #2218 from hswolff/npm-package-updates

Fix package.json scripts to be more in line with
Merge pull request #2205 from ErisDS/theme-debug

A first step towards theme debugging
abstract mobile interactions js

DRY up repeated code and simplify logic.
Merge pull request #2071 from samccone/sjs/show-error-on-import-failure

Show parse error message during a failed import
Merge pull request #2221 from samccone/sjs/clean-up-mobile-actions

abstract mobile interactions js