Specifying long_description_content_type (#33)

I was wondering why our description never showed up correctly on pypi.

Uploading to pypi errored telling me to specify this.

Co-authored-by: Michael Strain <michael.strain@ni.com>

Author: strainmike

setup.py

@@ -27,6 +27,7 @@ def get_long_description():
 setup(name="nifpga",
       description="Python API for interacting with National Instrument's LabVIEW FPGA Devices",
       long_description=get_long_description(),
+      long_description_content_type="text/markdown",
       version=get_version(),
       packages=find_packages(),
       install_requires=['enum34;python_version<"3.4"', 'future'],