Merge pull request #5 from dvp2015/master

test: fix tests for py3, tests passed

build: add pdf to .gitattributes

build: .gitignore and .gitattributes - some files are binary

build: add requirements.txt

Merge pull request #4 from jessecarterMOOSE/metastable_zaid

support new zaid for metastable nuclides

Merge pull request #3 from jessecarterMOOSE/run_unittests

make python scripts executable

use correct shebang statement

use np.inf for half-life of stable isotope in tests

run test cases as unittests

Merge pull request #2 from jessecarterMOOSE/uncertainties_v2.1+

update to work with uncertainties v2.1+

Use metastable states from wallet cards list