--filter option implemented.
Changes due to suggestions from @kcooney.
JavaDoc added.
"--filter arg" support added (as opposed to "--filter=arg").
Command line parser factored into JUnitCommandLineParser class.
Unit tests added.
Merge branch 'master' into filter-option

Conflicts:
	src/test/java/org/junit/tests/AllTests.java
Modification in response to code review from @kcooney and @dsaff.
More tests added.
crlf fixed.
API simplified. FilterFactory.parseArgs() removed. FilterFactoryParams made final.
Responses to code review from @dsaff.
Test added.
JavaDoc added.
FilterFactoryFactory renamed to FilterFactories and its methods made static.
ClassUtil renamed to Classes for consistency.
public keyword removed from methods of interface.
Merge branch 'master' into filter-option

Conflicts:
	src/test/java/org/junit/tests/AllTests.java
Command parsing errors internalized such that JUnitCore doesn't have to know about them.
Collect annotations for JUnit3 tests.

Necessary to support test filtering by annotation.
Treatments for parallel execution
synchronized filtered children in ParentRunner
simplified ClassRequest
Description#getChildren() JavaDoc