nl-NL translation: various improvements + update
Merge pull request #261 from xylographe/nl-NL

nl-NL translation: various improvements + update
translations: Remove unneeded spaces.
Fix exceptional resource leak CID18095
Fix exceptional resource leak CID18105
Fix exceptional resource leak CID18106
Fix exceptional resource leak CID18107
Fix exceptional resource leak CID18118
Fix exceptional resource leak CID18127
Fix exceptional resource leak CID18132
Fix exceptional resource leak CID18139
Fix exceptional resource leak CID18144
Fixed bug in output format in Timed Text 1.0
Fix exceptional resource leak CID18153
Fix exceptional resource leak CID18155
Fix exceptional resource leak CID18169
Fix exceptional resource leak CID18175
LanguageMaster: typo
da-DK translation: typo and new tag (FileXIsReadOnly)
fr-FR translation: typos, consistency, GitHub URL, and new tag (FileXIsReadOnly)