Added project source files

This commits adds a FileTreeWalker module and a FileDigestCalculator.
Modified FileDigestCalculator to output triples instead of strings.
Added module to reorder elements in triples
Completed example showing how to find duplicate files
Improved specification of modules directory.

Flux now looks for a modules directory in the following locations:
1. A modules directory in the current working directory
2. A modules directory in the same directory as the metafacture-core jar
   file
3. If the first commandline argument is -modules=PATH, this is used as
   the modules directory
Added a metamorph collector to output ranges.

The collector interprets the first literal it receives as a range start
and the second as a range end. The values are converted to integers and
for each number between the two an additional literal is generated.
Usage:
<range name="range">
  <data source="first" />
  <data source="last" />
</range>
update of MARC to EDM mapping
Merge pull request #72 from cboehme/specify-modules-dir

Improved specification of modules directory.
Merge pull request #73 from cboehme/range-expander-collector

Added a metamorph collector to output ranges.
Fixed issue #77.

GenericXmlHandler now outputs empty strings instead of null if no id
attribute is found on record elements
Fixed #79

ObjectToLiteral should not output null as record id.
Fixed #74

TimerBase no longer fails if closed without processing any data.
Fixed #82

Created a utility class for time related helper functions and moved non
time logging specific code from TimerBase. Added test cases.
Durations of length zero caused an exception.
Added project source files

This commits adds a FileTreeWalker module and a FileDigestCalculator.
Modified FileDigestCalculator to output triples instead of strings.
Prepare for move to core package
Removed modules which are not yet moved to core from flux-commands.properties
Fixed Java 6/7 compatibility issue
Added modules from Xoff/metafacture-extra.

Modules:
	- FileDigestCalculator
	- TripleReorder

Merge remote-tracking branch 'mf-extra/move-to-core' into adding-modules-from-mf-core

Conflicts:
	src/main/resources/flux-commands.properties