Made clone_structure public and fixed a spec context name problem
mentioned in #54.
Improvements to NMatrix.random
added reshapeBang function to reshape in place
tests added
new shape can now be passed in different ways
new shape can now be passed in different ways in normal reshape method also
reshape! not allowed on reference slices
more tests
Merge pull request #203 from rajatkapoor/reshapeInPlace

reshape! added for dense matrices, fixes #169, supercedes #192