Fixes an issure where the first part of an object file name is not
included, due to matching the rule for a section entry previously.
Reduce depedency on matching literal strings in sections which might
change depending on toolchain (ex. matching 'elf32-xtensa-le')
Make sure parsing rule succeeds for the entirety of the sections info
string by adding 'parseAll=True'.
Add test for sections info parsing.
This MR imposes some determinism in the mapping rule order in the output
file. For each section, the archives are arranged alphabetically
(ascending), and the mapping rules in each archive are arranged by
increasing specificity then alphabetically (ascending). The default
rules remain the very first rule for each section.
