Can apply browser executing types by command property or system property

[ansonliao]

Apply what browser want the test case run by command property or system property.

For example, the TestNG test class or TestNG test method maybe annotated by browser's annotation (let's say @Chrome, @Firefox).
Actually, sometimes want to ignore the browser annotation of TestNG class or TestNG test method:
want to run the all tests (can includes some package, some test group, etc.) by browser Edge, PhantomJs, so that can specify the browser types by command line:

mvn clean test -Dtest=MyTestRunner -DrunByBrowsers="EDGE, PHANTOMJS"

or set by system property by Java code:

System.setProperty("runByBrowsers", "EDGE, PHANTOMJS");