fixed old property name in the prefix addition
Add User Notification Upon Approval

Add user notification upon approval/activation

- Uses same logic as registration email to determine from address
- Refactor of various registration templates for readability
- Refactor of various registration tempaltes for HTML multipart
fixing page permission cache identifier bug to correctly identify when to use permission collection id; making 5.5.2.1 upgrade to 5.6.1
Merge pull request #929 from mkly/feature_user_approved_notfication

Add User Notification Upon Approval
Fix Bad Grammar

Change You're to Your in user_registration_approval_complete template
publish composer changes
Merge pull request #931 from mkly/fix_bad_grammar

Fix Bad Grammar
fixing block permissions in area names that had spaces
Merge branch 'master' of github.com:concrete5/concrete5
fixing block permissions in area names that had spaces
Merge pull request #927 from aghouseh/master

image helper enhancement bugfix - updated property name in the prefix addition
fixing potential bugs
body overflow bug fix
removed "Loader" line, it is unnecessary

removed "Loader" line, it is unnecessary because class extends a class which loads it
Checks for Help Icon Before Calling `popover()`

Checks for help icon `#ccm-page-help` before attaching
`$(document).click()` event
Fix Full Page Caching to Include Headers

Fix full page caching to include headers in `PageCacheRecord`

- Add method `PageCacheLibrary::getCacheHeaders(Page $c)`
- Refactor/DRY `PageCacheLibrary::outputCacheHeaders(Page $c)` to use
  `PageCacheLibrary::getCacheHeaders(Page $c)`
- Add method `PageCacheRecord::getCacheRecordHeaders()`
- Add method `PageCacheRecord::setCacheRecordHeaders($headers)`
- Set cache header record in `PageCacheLibrary::__construct()`

Design goal is to avoid changing the interface as I'm alread aware of
one page cache(for Redis) in the wild.

Slightly inefficient as it calls `PageCacheLibrary::getCacheHeaders()`
twice when caching a page.
Remove unuseful file

I don't think this .bak file should exists...
Fix (again) for badly converted short tag

This was already fixed, but commit #d2ac28e364fb1e0d464b1719f2f3fb30edd54f1e reintroduced this.
Allow TextHelper to be overwritten by a package

Fixes bug described here: http://www.concrete5.org/developers/bugs/5-6-1/cannot-override-texthelper-via-custom-package/
Fix `UserAttributeKey::getByHandle()` Return

Fix `UserAttributeKey::getByHandle()` return value to return false if
attribute key is not found. This maintains a consistent interface return
value as prior to change the first call before caching will returh -1
while following requests will return false

See
http://www.concrete5.org/developers/bugs/5-6-1
/userattributekeygetbyhandle-returns-1/