Lsl

* Fixed a build problem with lsl/reader/drspec.c found on some versions of OSX
* Various cleanups based on https://lgtm.com analysis
* Fixed a problem in the measurement set writer that caused CASA's listobs() to fail
* Clarified which version of FFTW3 is needed.

* Added UCF_USERNAME_RE to lsl.common.idf/sdf/sdfADP to make it eaiser to validate UCF usernames
* Added support for querying the MCS `mindelays.txt` file in lsl.common.metabundle/metabundleADP
* Added support for the XXCRCIYY, CRCI, and I-only DR spectrometer modes
* Several consistency fixes for the API in lsl.common.sdf/sdfADP and lsl.common.metabundle/metabundleADP

* Fixed a problem with displaying lsl.reader.errors under Python3
* Cleaned up SDF and IDF rendering to make it faster
* Fixed a problem in lsl.imaging.utils.ImgW that lead to a shift in source position with frequency
* Fixed a problem fitting a Gaussian to the point spread function in lsl.imaging.deconv

* Added a -v/--lwasv option to correlateTBN.py and tbnSpectra.py
* Added better input file type checking to the various "correlate" and "spectra" scripts
* Switched back to CDDIS for ionospheric data
* Fixed an error when setting beam/dipole mode for STEPPED SDFs
* Fixed a bug in updateLSLSSMIF.py when trying to revert a SSMIF
* Added a color keyword to the classes in lsl.common.busy and lsl.common.progress
* Added a new BusyIndicatorPlus class to lsl.common.busy
* Added a new DownloadBar class to lsl.common.progress
* Reduced the number of warning messages generated by STEPPED SDFs
* Added automatic updates of leap second information
* Changed the IDF and SDF modules to be more flexible on the styles of input coordinates

* Fixed a few problems with the scripts that ship with LSL
* Added support for time zone-aware datetime instances in lsl.common.datetime_to_mjdmpm() and mjdmpm_to_datetime()
* Added a utc_datetime attribute to lsl.reader.base.FrameTimestamp to provide a time zone-aware datetime instance
* Dropped the requirement that a beam be specified in lsl.common.sdf and sdfADP
* Fixed a deadlock condition that could occur during a DRXFile.offset()
* Fixed a bug in the DRXFile when dealing with small gaps in the data
* Updated lsl.reader.errors.SyncError to allow for reporting of non-Mark5C problems
* Update the documentation for lsl.common.idf, sdf, and sdfADP
* Added missing sub, isub, div, and idiv operators to lsl.reader.base.FrameBase
* Added a jd property to lsl.reader.base.FrameTimestamp to access the associated Julian day
* Updated the lsl.writer module to accept times as FrameTimestamp instances
* Updated the documentation in lsl.common.stations.Cable to make it more clear what attenuation and gain are

* Major API changes to put LSL under a uniform coding style
* Bumped the minimum Python version to 2.7
* Bumped the mininum SciPy version to 0.13
* Replaced PyFITS with astropy.io.fits
* Removed support for 32-bit systems in the lsl.common modules
* Added a new lsl.imaging.data module and classes to help store visibility data
* Added a new extension to speed up w-projection gridding
* Merged the non-windowed and windowed functions in the lsl.correlator extensions to de-duplicate some of the codebase
* Added support for reading CASA measurement sets with multiple spectral windows
* Added test suites for CASA measurement set support when the 'casacore' module is found
* Added support for astorpy.units.quantity.Quantity instances to lsl.misc.rfutil
* Updated the AIPY version requirement to >=3.0.1
* Updated the scipy version requirement to >=0.19
* Removed lsl.misc.mathutil.savitzky_golay since it was added in scipy v0.14.0+
* Added support for collecting usage data for LSL via lsl.misc.telemetry
* Updated to lsl.misc.ionosphere to IGRF13
* Dropped support for PyFFTW