Google Code-in 2014 Organization BRL-CAD Task Implement bu_scan_fastf_t() function to scan floating point values from strings

Implement bu_scan_fastf_t() function to scan floating point values from strings

completed by: Andromeda Galaxy

mentors: Sean, Daniel_R

This is a follow-on task for https://www.google-melange.com/gci/task/view/google/gci2014/5265491291537408

Following the analysis from that task, the objective is to implement the function described that has an argument for recording the number of characters scanned.

Implement the function making sure to robustly validate all function arguments. The function implementation should leverage existing API functions (e.g. bu_sscanf()) where warranted.

References:

https://www.google-melange.com/gci/task/view/google/gci2014/5265491291537408

Modify:

src/libbu/scan.c <-- create this
src/libbu/CMakeLists.txt <-- update this