Remove the need of naCacheBufferRange in naWriteBufferToData

[Manderby]

Some sort of caching all of a buffer is required but it should not happen with naCacheBufferRange. The NABuffer should be self-updating.

Also have a look at other occurences in naWriteBufferBuffer, naGetStringUTF8Pointer, naNewStringWithBasenameOfPath, na_AllocPNGChunkFromBuffer

Note to Manderby: The issue can be reproduced by running Karo Graph without CACHING_ALWAYS and opening a file by double clicking.