Added path dense definitions
Make sns-log channel world-accessible
Print when `sns' wrapper script signals a process
Fixup strings in message header

* Fix header hostname string termination
* Add process ident field
Transform messages
Some time handling
Plot with lines
Refactor message functions with macros
Fix some error printing
Store message item count in header as uint32_t

* This uses up some padding space after the uint32_t nsec variable
Per-message type ach_put() and ach_get() wrappers
Add weighted transform message
Option to persist the gnuplot
Generic source file for plugins

* Dispatch to appropriate functions based on command-line preprocessor
  symbol
Select indices to plot
Fix snsplot
C++ compat
Fix joystick message
Lazily call sns_init()
Reorder library link order for picky linkers