WebCL Conformance test suite update.

    Fixing issues mainly to take care of the review comments from reviewers.
    1. [Khronos Issue#10] Correcting testcases for DEVICE_TYPE_ALL & DEVICE_TYPE_DEFAULT. [SRA Issue#251]
    2. readKernel 's status code. [SRA Issue#123]
    3. Add test cases to test region overlap in enqueueCopy* API. [SRA Issue#267]
    4. Adding a test case to test for HTMLImageElement interop. [SRA Issue#269]
    5. Add slicePitch to enqueueWriteBufferRect with extension : WEBCL_html_image [SRA Issue#264]
    6. Renaming DATA_SIZE to bufferSize & providing appropriate values using variables.
    7. Usage of webCLEvent and webCLUserEvent, across files. [SRA Issue#272]
    8. [Khronos Issue#19] Change user interface of Test suite [SRA Issue#270]
    9. Add missed test cases of getInfo, to reflect spec. [SRA Issue#275]
    10. change -W to -w in build files. [SRA Issue#276]
    11. Change the usage of descriptor in HTML extension createImage API.[SRA Issue#260]
    12. Do not mess up with global variable in cl_utils.js create methods. [SRA Issue #280]
    13. [Khronos Issue#30] Refactor bindingTesting/queues/cl_commandQueue_enqueueWaitForEvents.html [SRA Issue #279]

    Contributors :
    SRI-B : Shilpa Shri, Sharath Kamath.
    SRA : Antonio, Steven and Igor.

    Details on changes is available at master_r01062014 branch:
    https://github.com/SRA-SiliconValley/webkit-webcl-conformance.git.