Important Note : As of 12/2/2015 I realized that a combination of Selenium Builder (http://seleniumbuilder.github.io/se-builder/) and Selenium Interpreter (https://github.com/SeleniumBuilder/SeInterpreter-Java) handles MOST of what I needed here. What they don't handle (although the NodeJS version comes closer than the Java one) is the ability to parameterize across multiple files and multiple browsers.
So instead of this being an interpreter (which Selenium Interpreter already handles pretty well) I'm making this an addition to interpreter to add those capabilities. At the same time I'm abandoning Selenium IDE for the newer and closer to compliant Selenium Builder.
An environment is basically just a configuration object for a WebDriver to abstract away the difference between running tests locally (against a local firefox, for instance) and remotely (against browserstack, for instance). Typically these are used in conjunction with @Parameterized.Parameters (for @RunWith(Parameterized.class) or @RunWith(ParallelParameterized.class)) so that the same test can be executed on each stack.
In the case of Selenium Builder Json files, there is only a single JUnit test, but we will execute it once, per environment, per Selenium Json file; we here leverage @Parameterized above to pull that off.
These can be found at src/test/resources (remote-test.json is a remote test, test-configuration.json is a local one)
testFilter If a testFilter param is set via system property or environmental variable (e.g. : -DtestFilter=.0021. ) then the SimpleSeleniumBuilderTest class will filter the set of all matching test cases down to only those that match the regular expression that was passed (either the name or the full file path much match the passed expression)
includeStackTraces If set to true (e.g. -DincludeStackTraces=true) the output on any test that fails due to an exception will include the full stack trace - by default, only the message is included.
retryPredicateClass If set (e.g., -DretryPredicateClass=com.timeinc.seleniumite.NotClickablePredicate) then whenever an exception is thrown for a given step, it will be checked with this predicate and if the predicate returns true, the step will be retried (up to 3 times, with 3 second waits between. I plan to parameterize this in the future, but not right now).
Seleniumite includes a built in class, NotClickablePredicate, which handles the common usage of a library like JQuery's BlockUI - if BlockUI happens to be up when the click is attempted, Selenium will just wait and then try again if this retry predicate is specified.
runSingleThreaded If set to true (e.g. -DrunSingleThreaded=true) then the tests will run globally single-threaded - useful for if you have test setup that cannot run multithreaded.