Update to latest libswiftnav.
CONSOLE: Fix observation view now that sender id != 0x2222
SOLUTION: Call filters even when num_sats < 5.

This is required so that the filter can detect the case there you have 5 satellites and then drop and regain the same satellite. The integer ambiguity needs to be reset so the filters need to know that there were momentarily only 4 sats.
NAP: Fix bug with new NAP version string reading.
NAP: Bound number of channels parameter to MAX_CHANNELS.

Don't want to exceed the limit compiled into libswiftnav.
Update libswiftnav and use the functions from sbp_utils to make baseline messages.

Fixes rounded TOWs in baseline messages.
RADIO: Update defaults, turn off ECC.
OBS: Only output observations aligned and decimated by obs_output_divisor.
OBS/RADIO: Update divisor to 5 (2Hz) for radio reliability.
Removing cruft.
Update windows closing properly now, no more seg faults
Refactor prompt windows and handlers in single window/handler that can
be used for both firmware update and console outdated prompts. Use for
firmware update prompt.
Use refactored UpdatePrompt for console outdated prompt
Use DMA for long SPI transfers with FPGA.
Fix __del__ and stop functions, call stop functions after finishing
bootload
Fix __del__ and stop functions, print elapsed time at end of write_ihx
Clean up run, call Bootload.stop and Flash.stop functions after flashing
is finished, change variables that don't need to be object attributes.
Clean up imports
Merge pull request #38 from gsmcmullin/spi_dma

Use DMA for long SPI transfers with FPGA.
Merge branch 'master' of github.com:swift-nav/piksi_firmware