Modify CakeSocket and HttpSocket so that the "protocol" parameter can be used to specify which protocol to use for creating sockets. These are protcols in the php "[a-z]://" wrapper sense. I also modified the test for these two files respectively to accomodate these new changes.
Unrelated to this bug, I added a "head" function inside of HttpSocket to go along with the GET/POST/PUT/DELETE/PATCH combination that's already present. Came in handy for me for deciding if I wanted to hit a resource with HttpSocket or not.
Fix coding standard violations
Remove unneeded comment out line that I just saw in compare view on GH
Fix HttpSocket test to actually reset protocols for correct test. Modify HttpSocket so that Https with non-passed in protocol doesn't set it to tcp and fail test.
Test for new HEAD function inside HttpSocket
Fix spacing to conform to coding standards
Add support for persistent SMTP connections.
Simplify tests, fix CS, remove `autoDisconnect` option.
Make `connect()` invoke authentication, make tests more explicit, add more tests.
Make SMTP auth reply code checks work properly.
Add some more exception message checks
Add `.` to the list of allowed characters.

This was missed when the email validation rules were relaxed in
dc34d80f6f622e883b8c7db9ef489bd514c8701f.

Fixes #4027
Merge pull request #3706 from MelvinRoss/httpsocketheader

Add support for specifying protocol in Cakesocket/HttpSocket.  Add HEAD function to HttpSocket
Update doc blocks.

There were a few trailing comments in #3706 that have now been
addressed.
Update version number to 2.5.3
Added NetBeans project folder to .gitignore

Refs https://github.com/cakephp/cakephp/commit/78fb9b559ab1745a7255583231694be99cec65c5#commitcomment-7077015
Fix cs error introduced after resolving merge conflict with master to 2.6
Merge pull request #4047 from ceeram/2.6-cs

Fix cs error introduced after master to 2.6 merge.
Update db_acl.sql to use correct column names.

The column names added in bb15271 were incorrect.

Fixes #4052
Add indexes to db_acl.sql in skel directory.

Copy changes in app/Config/Schema into the skel directory.

Refs #4052