Add a log_debug to the log script

[hoshposh]

Overview

Provide a DEBUG log level that also accepts a parameter to indicate if debug logging has been turned on.

# invocation example
log_debug "only want to see this when debug on" "true"

# expected output
[DEBUG] only want to see this when debug on

# Another invocation example
log_debug "only want to see this when debug on" "false"

# No expected output

[hoshposh]

Sorry, issue created by accident, closing