Update Package.php

Attribute keys were not displaying on the uninstall screen. There wasn't an error, they just didn't show.
Fix Redactor strings and translations

- Add customStyles text (for "Custom Styles" plugin)
- Translate "Remove Style" item
Fix translatable string

Translatable strings must be fixed, they can't contain concatenations and variable parts
typo in content.xml
Fix layout within layout editing.
tweaks to blog styles; adding picture tag support to content block
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0
Merge pull request #586 from Remo/patch-7

typo in content.xml
Reformat install controller.
Test for < php 5.2 on every page load, check for PDO on install.

fixes #73
Check for the actual minimum version.
improved file manager on smaller screen sizes
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0
Assert my icon ideals upon bootstrap editable. fix #591
updating sample content for blog, removing some styles that were screwing up smaller headers
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0
Update type_form.php

Renamed the labels to match with Facebook.
Update form.php

Changed case of facebook to Facebook.
Merge pull request #602 from skybluesofa/patch-6

Update form.php
Update controller.php

Updated case from facebook to Facebook in multiple places.