Exiting with 1 when Exception::getCode() returns non-integer values.

From php.net/exception.getcode
> Returns the exception code as integer in Exception but possibly as other type in Exception descendants (for example as string in PDOException).
Merge pull request #3809 from renan/2.5-non-integer-exception-code

Exiting with 1 when Exception::getCode() returns non-integer values.
cs correction
Fix identifier typos
Fix more doc block errors in lib/
Tidy up and simplify travis.yml file.
Merge pull request #3829 from cakephp/api-doc-fixes

API doc fixes
Add pluralization rule for "stadia".

Refs #3830
Merge pull request #3832 from ADmad/2.5-inflector

Add pluralization rule for "stadia" to uninflected list.
Revert "No truncate when drop table."
Relax email validation rules even more.

While filter_var() allows a number of email addresses that
Validation::email() does not, it misses out of email address that
contain IDN host names, and unicode mailboxes. Both of these are
generally deliverable, and should be permitted. filter_var() also fails
on local mailboxes like `root@localhost` which is useful in the context
of cron jobs.

Fixes #3742
Fix failing test.

CakeEmail now has a default validation pattern.

Refs #3742
Merge pull request #3840 from cakephp/issue-3742-relax-email

Relax email validation rules even more.

Fixes #3742
Merge pull request #3838 from cakephp/revert-3646-no-truncate-fixture

Revert "No truncate when drop table."

Not truncating tables when they are created causes a number of 
issues in ControllerTestCases as indicated by the comments in #3646 post merge.
Fix additional missing API doc tags.
Make PHPCS build passing again.
Merge branch 'master' into 2.6
Update code examples to be consistent with other docs.
Remove mention of Role/default as it doesn't exist.

The default role merging was removed in
3abfaeecf30b845ac3a309f011bc460222a923b4 and shouldn't be mentioned in
the docs.

Fixes #3871
Correct doc blocks according to cs guidelines.
Remove superfluous empty lines.