Changed Enclosed runner to ignore abstract classes. Before this change, an abstract enclosed class caused jUnit to throw an exception.
Implemented the changes proposed davidhart82
Changed the filtered collection to an ArrayList from an HashSet to avoid re-ordering of
existing order-dependant test suites, as per the comments of kcooney.
Implemented the changes proposed by kcooney:

1) Now passing classes.length to the constructor of ArrayList
2) Code style adjustment (no spaces before the = in an assignment)
Added abstract-avoiding behavior to the javadoc.
Treatment Of Long Variables and thread-safe constructor for List
Next version is 4.12
Ready to collect release notes for 4.12
Added different implementation for Null Sorter test

Added an extra test case providing an alternative implementation for 
the getMethodsNullSorter test case.

The new implementation passes when coverage analysis using jacoco is
enabled, whereas the old one incorrectly fails.

The new approach only checks the order of methods that are of interest
(i.e., not looking at irrelevant extra methods that the coverage
analyzer might generate).

Furthermore the new approach avoid the 'sensitive equality' test smell
by replacing toString-based equality by actual equality.
fixes for #544 and #545
Note and link to wiki
one tmp file per test, reasons for volatile and daemon thread
A fix for semicolon.
TemporaryFolder instead of File.createTempFile()
Extract test case refactoring for subclass NullSorter
Created a separate test case for null sorter applied to methods from 
the *sub* class. Fixed this test case so that it still works well
under (jacoco) coverage.

Incomplete - task : Resolve sensitive equality in MethodSorter test. 
Renamed getXYZ test cases to testXYZ test cases.

Incomplete - task : Resolve sensitive equality in MethodSorter test. 
Renamed Dummy class to ClassWithoutSorterAnnotation

Incomplete - task : Issue 551: Resolve sensitive equality in
MethodSorter test. 
Fixed MethodSorter test case for default sorter.

Adjusted test of Default Sorter so that its equality check only 
deals with actually declared methods, fixing issue 551 for this
test case.

Incomplete - task : Issue 551: Resolve sensitive equality in
MethodSorter test. 
Fixed MethodSorter test case for ascending sorter.

Adjusted test of Ascending Sorter so that its equality check only 
deals with actually declared methods, fixing issue 551 for this
test case.

Incomplete - task : Issue 551: Resolve sensitive equality in
MethodSorter test. 
Uniform naming of Dummy classes

Incomplete - task : Issue 551: Resolve sensitive equality in
MethodSorter test.