Enable GitLab CI and address issues identified

* Add missing `.gitignore`
* When some BASIC test programs were added, the required update to
  `.gitattributes` was overlooked
* Remove a small number of recent whitespace errors so that future
  introductions of new ones can be automatically detected and flagged
9 jobs for CrossCompilationSupport in 28 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Static Analysis
passed #38429
cross
gitattributes

00:00:00

passed #38430
cross
gitignore

00:00:00

passed #38433
cross
head_log

00:00:00

passed #38435
cross
head_whitesp

00:00:00

passed #38431
cross
license

00:00:00

passed #38434
cross
makefile

00:00:00

passed #38432
cross
versionnum

00:00:00

 
  Rom
failed #38436
cross allowed to fail
rom_BCM2835

00:00:22

 
  Cleanup
passed #38437
cross
cleanup

00:00:01

 
Name Stage Failure
failed
rom_BCM2835 Rom
Error running make export (hdrs) on module 'HAL_BCM2835'.
Error running make export (hdrs) on module 'FileCore'.
Error running make export (hdrs) on module 'ADFS'.
Error running make export (hdrs) on module 'RamFS'.
Error running make export (hdrs) on module 'SCSIFS'.
Error running make export (hdrs) on module 'SDFS'.
------------------------------------------------------------------------------
Cleaning up project directory and file based variables
ERROR: Job failed: exit status 1