By Luke T. Shumaker
* origin/merge-requests/328:
  functions: support "ARM zImage" compressed files
  functions: clean up _zboot_cat()
  functions: create a decompress_cat() function
  functions: improve comments about kernel version sniffing
  functions (API change): move zboot algo detection to detect_compression()
  functions: detect_compression: use printf instead of echo
  functions: detect_compression: call out to `od` just once, organize the code into a case-block
  shell: use the 'functions' file to implement _detect_kver()

See merge request !328