v2.5.5

Full Changelog

Closed issues:

• MSG_INIT_BASE / Hotstart with known Position #681
• Problem when casting messages from callback in C #611

Merged pull requests:

• Use piksi_tools master in benchmark #689
• Add source to gal eph #688
• Added additional checks for tools in the Makefile #684
• [ESD-1238] Do not call nullary constructors in Haskell ToJSON #680
• Automated Travis benchmark [ESD-1158] #667
• Log a warning for dispatch exceptions #653