add Vishal's master-worker code
Merge branch 'devel' into feature/master-worker
added README for Master/Worker example
Merge branch 'devel' into feature/master-worker
Merge branch 'devel' into feature/master-worker
fixx attrib deepcopy
simplify deep copy
fix deepcopy, again
acceept None as flag
remove tabs; fix loop detection
add sagapython-version
attempt to fix #351
Merge branch 'devel' into feature/master-worker
convert an error message into a more appropriate debug log entry
fir tcsh prompt aggression
get_exit_code in the shell adaptor now returns None if no exit code is available (instead of raising an exception)

This closes #350
remove an error check which screwed with proper error reporting
use "file://" as default schema
add some default settings
add some default settings