removed highlighting of boreholes again due to severe colour-lookup-table issues; tidied up lots of other very small things

fixed issue #26 ; fixed problem with CMAKE not finding VTK_DIR if other small libraries are build at the same time.

re-implemented vtu read- and write-functionality using boost xml and property trees. compressed data is not yet supported.

Dmitri Naumov authored 12 years ago and Karsten Rink committed 12 years ago

Adding findDataArray() and getXMLAttribute() helper functions for parsing boost's ptrees.

added open/save/remove buttons in tab-widgets; added reload button for recalculating colorlookup-table for active scalar; fixed issue with incorrect display of active scalar array name; fixed issue with mesh quality not being scaled correctly; added scheme for enabling access buttons only when needed