8.9.0+0.6.1: Version 0.6.1:

CHANGES:

• [serapi ] Add Parse command to parse a sentence; c.f.
  #117
  (@ejgallego) (cc: @yangky11)
• [sercomp] Add "print" --mode to print the input Coq document
  (@ejgallego) (cc: @Ptival)
• [serlib ] Serialize Universe.t (@ejgallego, request by @yangky11)
• [sercomp] Merge sercomp and compser, add --input parameter to sercomp
  (@palmskog) (cc: @ejgallego)
• [serlib ] Much improved support for serialization of Environ.env
  (@yangky11 and @ejgallego c.f. #118)
• [serapi ] Make sure every command ends with Completed, even if it produced
  an exception (@brando90 and @ejgallego c.f. #124)
• [sercomp] Add --mode=kexp to output the final kernel environment.
  (@ejgallego c.f. #119)
• [serlib ] Serialize more internal environment fields (@ejgallego c.f. #119)
• [serlib ] Improvements in serialization org (@ejgallego)
• [serlib ] Serialize kernel entries (@ejgallego @palmskog)
• [serlib ] Fix critical bug on Constr deserialization; reported by @palmskog,
  fix by @SkySkimmer.
• [sertop] Fix backtrace printing when using --debug (@ejgallego)
• [serlib ] Don't serialize VM values (@ejgallego, bug report by @palmskog)
• [serapi ] Output location on tokenization (@ejgallego , idea by @palmskog)
• [serapi ] Add basic documentation of the protocol (@ejgallego cc #109)