The port from HSC of SafeClipAssembleCoaddTask has left some documentation and code quality changes to be made. Specifics include:

• In the process of porting, functionality was added which allowed users to specify additional mask planes to be converted to pixel flags. However this was fundamentally incompatible with the flag handler functionality that LSST was currently using. PixelFlags was thus modified to allow SafeClipAssemble coadd to work with the user defined masks, but that made it fundamentally different than the other plugins. In the future this plugin should be brought more in line with all the other measurement framework. This will most likely involve rewriting sections of the measurement framework, to add the ability for users to more directly set runtime behaviors of the measurement plugins (such as specifying non default mask planes to work with).
• Because PixelFlags could no longer use the the flag handler framework, sections of the SafeCentroidExtractor had to be duplicated within PixelFlags. This duplicated code is non-ideal and should be rectified. Possibly in the process of rewriting the measurement framework, the utils could be expanded to have convenience methods to access functionality when not using flag handlers
• As with all of the measurement framework, PixelFlags needs better documentation. This includes some line to line comments, but more importantly the over all functionality of the routine needs documentation. This includes: what the routine does; how it works; and why various design decisions were made