Added pip install funcsigs

.travis.yml

@@ -36,6 +36,7 @@ before_install:
 # Install packages
 install:
   - conda install --yes python=$TRAVIS_PYTHON_VERSION numpy scipy nose pytest matplotlib pytest-pep8 pytest-cov mpmath pillow numba
+  - pip install funcsigs
   - pip install numdifftools
   - pip install coveralls
   - pip install codecov

requirements.txt

@@ -5,4 +5,4 @@ numdifftools>=0.2
 scipy>=0.9
 matplotlib
 mpmath
-
+numba