failing tests on octave / windows

[Remi-Gau]

abspath seem to lead to many errors: better switch to using bids-matlab file_utils

failure: regexp: \ at end of pattern at position 1 of expression
  abspath:95 (D:\github\CPP_BIDS\lib\utils\abspath.m)
  checkCppBidsDependencies:27 (D:\github\CPP_BIDS\src\utils\checkCppBidsDependencies.m)
  checkCFG:189 (D:\github\CPP_BIDS\src\checkCFG.m)
  createFilename:38 (D:\github\CPP_BIDS\src\createFilename.m)
  setUp:14 (D:\github\CPP_BIDS\tests\utils\setUp.m)