added target for src/test/*
Merge branch 'develop' into feature/issue-391-move-tests
moved agrad tests to src/test/unit/agrad; left distribution tests in place.
moved command tests to src/test/CmdStan
moved io tests to src/test/unit/io
moved math tests to src/test/unit/math
moved mcmc tests to src/test/unit/mcmc
cleaning up mcmc tests
moved memory test to src/test/unit/memory
moved meta test to src/test/unit/meta
moved model test to src/test/unit/model
moved prob tests to src/test/unit/prob
moved models tests to src/test/CmdStan/models
disabled 5 model tests that have failed for v2.1.0
moved distribution tests to src/test/unit-distribution/ and src/test/unit/distribution
fixed base_hmc_test.cpp
adding deprecation message
moved gm tests to src/test/integration, src/test/CmdStan, and src/test/unit/gm
trying out a different secondexpansion
updating mcmc_writer_test to match changes in makefile