remove other un-needed files

[huangruizhe]

Remove un-needed files, which are not mentioned in any Makefile or not included in any other src files.

First, in kaldi/src/ directory and its subdirectories, the following shell script finds out all candidates which are *.cc or *.h files whose basic file names (without the extension) are not mentioned in any of the following:

• Makefile*
• *.mk
• kaldi/src/configure

find-non-used.txt (change extention to .sh and chmod+x before use)

Here are 6 files we found:

• src/chain/context-dep-topology.h
• src/cudamatrix/cu-kernels-ansi.h ----x
• src/decoder/decodable-mapped.h
• src/decoder/decodable-sum.h
• src/util/basic-filebuf.h ----x
• src/util/kaldi-cygwin-io-inl.h ----x

Second, we use the following script to double-check the candidates and see if they are referenced by others but not explicitly mentioned in Makefiles:
grep -r base_name kaldi/src/
The "false-positives" are those marked by "----x".

At last, we remove the remaining 3 files.

[danpovey]

Thanks for finding these.
Please update your PR to un-delete the two decodable headers. They may be useful for something in future, and may possibly be used by people already for things like system combination.

[huangruizhe]

The two decodable headers are un-deleted, while their version histories are preserved.