Merge pull request #2 from sqs/use-same-package-in-test

Use same package as non-test files in string_test.go
Example apps compile now, although one of them hald faults while running. Baby steps.
Use github import paths.
Merge pull request #3 from sqs/Allow_use_of_external_JSContextRef

WrapContext func to allow use of externally obtained JSContextRef (e.g., from WebKit)
Tests are passing