[hack] parse strings and objects
[hack] parse strings and objects

Summary:
See format at https://facebook.github.io/watchman/docs/bser.html

Similar to arrays, but now requiring strings for field names. Objects
are encoded

  [tag][number of fields][fields]

Where the tag is `\x01` and each field is of the form:

  [name][content]

And each name is a string with form

  [tag][length][content]

where the tag is `\x02`, the length is a BSER integer, and the
content is just a byte array.

Reviewed By: mbouaziz

Differential Revision: D3809383

fbshipit-source-id: 09d91465036e22ad5d713a2e846795866331e1f3

TiddoLangerak/flow,gabelevi/flow,AgentME/flow,jamesgpearce/flow,ForbesLindesay/flow,MichaelDeBoey/flow,nmote/flow,mroch/flow,nmote/flow,ForbesLindesay/flow,MichaelDeBoey/flow,gabro/flow,JonathanUsername/flow,jamesgpearce/flow,mroch/flow,ylu1317/flow,samwgoldman/flow,ForbesLindesay/flow,mroch/flow,AgentME/flow,ylu1317/flow,nmote/flow,samwgoldman/flow,JonathanUsername/flow,popham/flow,nmote/flow,AgentME/flow,facebook/flow,jamesgpearce/flow,claudiopro/flow,facebook/flow,popham/flow,JonathanUsername/flow,MichaelDeBoey/flow,ylu1317/flow,samwgoldman/flow,TiddoLangerak/flow,gabro/flow,nmote/flow,jamesgpearce/flow,AgentME/flow,ylu1317/flow,mroch/flow,TiddoLangerak/flow,popham/flow,gabelevi/flow,mroch/flow,TiddoLangerak/flow,fletcherw/flow,samwgoldman/flow,MichaelDeBoey/flow,fletcherw/flow,facebook/flow,gabro/flow,claudiopro/flow,gabelevi/flow,JonathanUsername/flow,gabelevi/flow,ForbesLindesay/flow,samwgoldman/flow,fletcherw/flow,gabro/flow,MichaelDeBoey/flow,gabelevi/flow,claudiopro/flow,JonathanUsername/flow,samwgoldman/flow,JonathanUsername/flow,fletcherw/flow,samwgoldman/flow,popham/flow,popham/flow,gabelevi/flow,facebook/flow,popham/flow,jamesgpearce/flow,facebook/flow,jamesgpearce/flow,JonathanUsername/flow,claudiopro/flow,TiddoLangerak/flow,gabro/flow,facebook/flow,ylu1317/flow,claudiopro/flow,mroch/flow,ForbesLindesay/flow,fletcherw/flow,mroch/flow,fletcherw/flow,gabro/flow,nmote/flow,gabelevi/flow,nmote/flow,facebook/flow,popham/flow,ForbesLindesay/flow,jamesgpearce/flow,AgentME/flow