First official release for pip

First official release for use with pip, see README.md for more info on what this package can do.

NOTE on pySLALIB: For complete compatibility pySLALIB should be installed. Currently this is set to optional as it is necessary to have a FORTRAN compiler available. This can be somewhat cumbersome on windows, therefore pySLALIB is set as an optional package. The slalib() function will print a warning if it does detect that pySLALIB is not installed and a value of 1 will be returned.