was using nb[2] twice with airDtoS (thanks Hans Johnson)
• Added nrrdEnvVarDefaultIoHeaderDoubleExcessPrecision so that you can
fixing spelling in comments
hest/test/ex6 still needs a C-locale-emulation overhaul
progress towards C-locale-emulation
making commented code more visibly commented (re pragmatic-fpio: so that non-FP-IO code isnt needlessly modified)
fixing spelling in comments (unrelated to purpose of pragmatic-fpio branch)
str2fp now only saves to caller-supplied variables if strtof/strtod consumed whole string