check the buffer length read in constant meta, if it's not equal to t…

[vishal1132]

There was an issue with using the LoadKnowledgeBaseFromReader function on the *ast.KnowledgeLibrary when passing the *tar.Reader which had the *gzip.Reader underlying in the r of *tar.Reader which should ideally not be passed because of how the *gzip.Reader's decompressor's read() method is implemented and how the library is not reading until EOF but actually reading a specific set of bytes, and for any such usecase the *gzip.Reader is ideal, where there is a need to read a chunk of bytes and not until EOF.
But this debugging(I believe) could be made faster if we had the buffer read check on Constant Meta's ReadMetaFrom implementation. Basically because the decompressor had some state which had the toRead method which will be updated when the step() function which takes the pointer to the decompressor and changes it's state, but since it read less number of bytes than it had to. The new 8 bytes were read from different set of bytes, which would attempt to read from a different length of bytes array. Which was the issue but could have been easier to debug if there was a check in the package (according to me.).
But in any case this doesn't compromise the correctness of the flow, and seems like a useful check. WDYT?

[newm4n]

I am very sorry, I committed the code wrongly. I should be
readCount, err := reader.Reader(byteArr)

Forgot to puth the collon there. Coud you change it accordingly and push again.

[newm4n]

I have accepted this pull request but my attempt to merge it fails.
Its my mistakes, thus I copy you change directly and incorporate it into master.
Thanks a lot for your contribution.