gr: added API macros for noaa and pager, also renamed the ones for digital and vocoder to be consistent
digital: added symbol visibility defines to gr-digital, builds on MSVC and linux
gr-digital, gr-trellis: Fixing gr-trellis to work with constellation now that it is in gr-digital.
gr-digital: formatting constellation block for our style; adding 8PSK constellation.
gr-digital: updating build for consetellation object move.
gr-digital: moved consetellation object into gr-digital space.