gnode: fix entering the REPL with other flags are passed in as well

So this now works as expected:

  $ gnode -i

Or passing in any flags when going into the REPL should work fine as well
gnode: print out the args for debugging purposes

When the GNODE_PRINT_ARGS env variable is set.
README++
test: initial CLI tests
gnode: proxy the exit code from the child node process

Duh!
test: more CLI tests
add .travis.yml
test: make test/cli/check.js work with native generators

Apparently checking for `'Generator' == g.constructor.name` doesn't work
in native V8. We should probably change that check in `co`...
README++
README++
test: add `process.argv` test
test: add stdin test
test: use `semver` module to test node version
test: remove dead code
index: strip away the hashbang before feeding the script to esprima
index: add comment
v0.0.4
index: match the strip shebang logic from lib/module.js
index: don't add the global require .js hook in some cases
fallback: make `process.argv` only have 1 entry in the repl