Updates to make rails 4 happy with minitest 5:

+ Namespace changes, overhaul of runners.
+ Internal ivar name changes
- Removed a logger globally applied to tests that spew everywhere?!?
+ Override Minitest#__run to sort tests by name.
+ Reworked testing isolation to work with the new cleaner architecture.
- Removed a bunch of tests that just test minitest straight up. I think these changes were all merged to minitest 4 a long time ago.
- Minor report output differences.
tweak dependencies
oops. I should have only required minitest, not minitets/autorun. muscle memory.
exit with non-zero to signal failure
add test for skip_before_filter with condition
Support array as root element in JSON
Also support extensions in PostgreSQL 9.1, because this has been supported since 9.1.
Remove unnecessary code, because this extension is created on demand in hstore_test.rb.
restore ability to return nil from asset_host proc, add test
this variable is used, so we don't have to use double assignments
just call the class method since we know the callbacks are stored at the
class level
Revert "Merge pull request #10600 from aditya-kapoor/code_refactor"

This reverts commit 8ce3c1e5dde9fb180813e4d89324db03da110b13, reversing
changes made to f93da579ce7f77dbd58b9a2165861aee265b8c93.

Reason: It slow down the running time.

require "diffbench"
load 'output_safety.rb'

N = 10000
b = ActiveSupport::SafeBuffer.new("hello world")
DiffBench.bm do
  report "capitalize in safe buffer" do
    N.times do
      b.capitalize
    end
  end
end

> git checkout  069ea45; diffbench bench.rb;
diffbench bench.rb;diffbench
bench.rb;diffbench bench.rb;diffbench
bench.rb;diffbench bench.rb;diffbench
bench.rb;

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.009733)
Before patch:   0.010000   0.000000   0.010000
(  0.007702)
Improvement: -26%

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.009768)
Before patch:   0.010000   0.000000   0.010000
(  0.007896)
Improvement: -24%

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.009938)
Before patch:   0.010000   0.000000   0.010000
(  0.007768)
Improvement: -28%

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.010001)
Before patch:   0.010000   0.000000   0.010000
(  0.007873)
Improvement: -27%

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.009670)
Before patch:   0.010000   0.000000   0.010000
(  0.007800)
Improvement: -24%

Running benchmark with current working tree
Checkout HEAD^
Running benchmark with HEAD^
Checkout to previous HEAD again

                    user     system      total
                    real
----------------------------------capitalize
in safe buffer
After patch:    0.010000   0.000000   0.010000
(  0.009949)
Before patch:   0.010000   0.000000   0.010000
(  0.007752)
Improvement: -28%
Merge pull request #10504 from kennyj/support_pg_91

Also should supports PostgreSQL 9.1 about extensions.
require things we need
Merge pull request #10591 from acapilleri/cond_callback_test

add test for skip_before_filter with condition
add failing test exposing mysql adapter tinyint bug

in myself, a column with type TINYINT(N) where N > 1 can be used to
represent an integer, but the rails mysql adapter refuses to interpret
as anything but a boolean.
tiny types should only be integers when the length is <= 1. fixes #10620
Remove trailing line break

If you generate a fresh app without ActiverRecord, this template
exhibited a lone trailing line break. My watchful pre-commit hook
told me about it so I've fixed it here.
Fix detection of engine in rake db:load_config
Broken by d1d7c86d0c8dcb7e75a87644b330c4e9e7d6c1c1
Merge pull request #10640 from joelcogen/master

Fix detection of engine in rake db:load_config