Revert "Merge pull request #124 from dstine/logback-debug"

This reverts commit bd88d3ed580a4f60dc54c3293eb42aee5ea73148, reversing
changes made to 79a410f919fd5e3dc66fa1e6cf7ebb945c27a80f.
Fix ThrowableProxy unit tests

Modified the regex patterns in RootCauseFirstThrowableProxyTest and
ExtendedThrowableProxyTest to find any packaging info in the throwable's
stack trace, including inexact matches.

On Cloudbees Jenkins, these tests were failing because they were looking
for an exact match of the JUnit package but only found an inexact one.

(cherry picked from commit dcfb0a056f3e084d8395b33f4d4acdb5d7ea7dba)
Merge pull request #148 from leonardossz:fix-LOGBACK-842

fix for LOGBACK-842

(cherry picked from commit 9ff887679130d112382c5985367fda412fa01dff)
Be extra lenient for non-Sun JDK perf tests

The slack factor for non-Sun JDK performance test in PackagingDataCalculatorTest
was not lenient enough for the small virtual nodes on Cloudbees Jenkins.
Some people were also reporting test failures here by a few percentage points
(on their slow development machines).

Bump slack factor from 10 to 15

(cherry picked from commit 841d22aea4232777ad57d8174341495c792a4d7e)
Fix RecoveryCoordinatorTest

Use new instance of RecoveryCoordinator in each test. Otherwise, the timestamp
of the next call to isTooSoon() could happen well after the backoff threshold
on slow machines (such as small nodes on Cloudbees Jenkins), causing false
test failures.

This also renames and refines the individual tests.

(cherry picked from commit 409ba25961d40b4a6f7268ea596190a1abd4b935)