get rid off passing around loggers
more log passing cleanup
more log cleanup
more log passing removal
more log cleanup
Merge pull request #489 from stdweird/broken_regtest_submisison

get rid off passing around loggers
raise can't be reached with EasybuildLogger
move toolchain option validation to tools.options
cache ppn value so no temp connection to the PBS server is set up on every job submission
fixed minor remarks
Merge pull request #492 from boegel/ppn_caching

cache ppn value
Merge pull request #491 from stdweird/broken_regtest_submisison

move toolchain option validation to tools.options