Logger: support for "fragmented" logs

Added logFragmented, that will flush message to log without appending EOL.
Calling log after that will add EOL. Timestamps are added only on first call to
log(). So doing something like

logFragmented('Hello... ')
logFragmented('fellow... ')
log('human.')
log('How... are... you?')

Will result in:

[timestamp] Hello... fellow... human.
[timestamp] How... are... you?
Added process id to Logger
Closed #120
Closed #121; minor layout fixes