vere: bytecode hints & memory hints

[DaneBettis]

This branch is based on /next/vere

I am adding a new hint %xray. %meme will be added in my next PR, after this one makes it into master.

%xray reports the c-vere bytecode of the hoon expression it wraps.

%meme will report the current memory statistics at the moment it is encountered. In other words, %meme doesn't wrap any computation, so much as it triggers a memory report be printed when it itself is evaluated. To see changes in memory stats over time, just wrap various hoon expression in %meme calls, and they will report in order as they are encountered.

Like %bout, %nara and %hela, %meme and %xray will optionally be able to print user-supplied data.

[jfranklin9000]

litteral -> literal