[INTERNAL, TEST] File: removed old streams and formats, removed tests

	Remarks: the whole test_file went away, some components inside the file module are not tested.
[INTERNAL, API] Stream: reorganized read/write, chunking, tokenization

Squashed commits:
[FIX] String: removed forwards and references to read() and write() - will use the new streams
[47cd18a] [FEATURE] Stream: imported FileFormatExtensions and format tags
[4b2590d] [FIX] Stream: re-included concept_stream.h
[0bc4628] [FIX] File: changed the ordering of includes in file.h
[5a394f2] [INTERNAL] File/Stream: moved file_format_mmap into streams, pulled out format guessing code and marked it as deprecated
[API] Stream: added read() for containers
[TEST] LexicalCast: removed superfluous typenames