Updated readme

Updated an invalid link to "Spesifikasjon for skjermkartografi".
Updated readme

Updated both links to kartverket, and kept the same domain name in both
(kartverket, not statkart).
Render railway and tramway according to ISSOM
Add symbols for cultural heritage
Dashing of trails according to ISSOM
Canvas background changed in JOSM r7110
Show graveyard similar to cemetery
Add styling of fences, cableways and cliffs
Make signpost selectors more robust and specific to Marka
Add selectors for milestone and pithole
Merge updated links to kartverket.no