CSP with no metadata failed at read with MSVC10 64 bits

Errors at runtime : 
``The specified transform file '(...)rsr_linear_3D_NoMetadata.csp' could not be loaded. malformed 3D csp lut, couldn't read cube size``
or
``The specified transform file '(...)rsr_linear_1D_NoMetadata.csp' could not be loaded. malformed 1D csp lut``

The problem seems to be related to an msv10 bug with seekg.
See ["std::fstream use 32-bit int as pos_type even on x64 platform"](http://connect.microsoft.com/VisualStudio/feedback/details/627639/std-fstream-use-32-bit-int-as-pos-type-even-on-x64-platform)
(I tried several workarounds to patch msvc10, including the one decribed in the link above, but no one worked for me)

This pull request remove the use of seekg and add a condition to handle the "no metadata case".