previously we checked the offset was not inside the table (correct thing to check), however this is only a special case of the more general issue (cross reference offsets are wrong). we move handling for this into the pdf token scanner. if we attempt to read an object at an offset and it fails we brute force the entire file to find correct offsets. we also needed to add handling to make sure we don't attempt to use stream length tokens if we're brute-forcing since we can't look up indirect references for length.
if the %pdf version header comment is offset from the start of the file the cross reference offsets will also be wrong by that amount. this change updates the cross reference location logic to use the offset from the located version header.
some documents declare stream objects without an endobj marker at the end of the stream. if a new obj token is encountered after reading a stream we reset the scanner to the object number token and return the stream.
don't cache objects parsed if their offset doesn't match the cross-reference offset, unless the object was parsed by a brute-force search operation. this is because 1 object may lie in 2 streams, 1 valid and 1 invalid. If the invalid stream is parsed first for another object then the valid stream will never be read.
to make the project more useful and expose more usable classes we're rearchitecting in the following way. code used to read fonts from external file formats like truetype, adobe font metrics (afm) and adobe type 1 fonts are moving to a new project which doesn't reference most of the pdf logic. the shared logic is moving to a new flat-structured project called core. this is a sort-of onion type architecture, with core being the... core, fonts being the next layer of the onion, pdfpig itself the next. this will then support additional libraries/projects as outer layers of the onion as well as releasing standalone version of the font library as pdfbox does with fontbox.
* while the pdf specification says stream data should follow a newline following a stream operator some files have only a carriage return following the stream operator.
* since comment tokens may appear inside an array or dictionary we ignore them if they occur here since they will break interpretation of the dictionary or array contents.
support both xobject and inline images. adds unsupported filters so that exceptions are only thrown when accessing lazily evaluated image.bytes property rather than when opening the page.
treat all warnings as errors.