blas install docs, other install polish
trivial makefile grooming
auto-configure linux/osx build differences

- set cxx as needed (clang++ on os x)
- set stdlib flag for os x 10.9 (CUDA libc++ workaround)
- link ATLAS properly for non-MKL installation whether linux or os x
Merge pull request #305 from shelhamer/install-doc-blas-platform

Document BLAS install, tailor Makefile and Makefile.config to platform
add test demonstrating weird boost RNG issue when sampling from a
gaussian followed by a bernoulli
add analogous test for uniform instead of gaussian
cleanup log messages
add bernoulli*bernoulli test
call caffe_set_rng at the end of each vRng function to maintain state
fix bernoulli*bernoulli test, now all pass
comment to explain the purpose of Caffe::set_generator
cleanup test_math_functions
make rng_ a private member of Generator
cleanup RNG unit tests
gpu_hamming_distance fails unit test with fixed RNG; mark it NOT_IMPLEMENTED
with TODO to fix and disable its unit test
make RNG function names more similar to other caffe math function names
make RNG function outputs the last argument per Google C++ style guidelines
have rng_stream initialize RNG if not already initialized
add analogous caffe_gpu_rng_* functions for gaussian and uniform, and
add test cases
change *Plus* tests to *Times* tests because the Plus tests don't
actually check for uncorrelated RNG results