Initial cut at an "exported variables" (exvar) package.

This handles integer-valued vars in a singleton struct, and exports functions
for incrementing, setting and getting those vars, as well as rendering all the
vars in a standard format.

Demonstrate the use of the exvar package in the http/triv server.

R=dcross,r
APPROVED=r
DELTA=122  (122 added, 0 deleted, 0 changed)
OCL=27617
CL=27622
4 files changed
tree: cfa851901e36a3a35b7d9ba6555c957f97308ac5
  1. doc/
  2. include/
  3. lib/
  4. pkg/
  5. src/
  6. test/
  7. usr/