Corrected data output format fixed

This patch changes the output format of the data files for xPPSOffset
corrected TIC measurements.  Now, the format is similar to the TIC
data file format, so it can be easiliy read back in by analyseTIC.py and
reploted at a later time (without xPPSOffset data present).
Added mkCLKns.sh

mkCLKns.sh extracts the "StationClkOffset" value, called CLK(ns) or
rx_clk_ns by CSRS, and stores it in a file next to the CSRS .zip
bundle using the same filename format as xPPSOffset and pvtGeo block
exports I created from the SBF data logs.
Added FFT to anlayseTIC

Still WIP, but I want to check in this code for the time being.
Merge branch 'nu' into dev