#64 keep/flush lines in cscope result buffer

[lgfang]

Sometimes there are lots of entries in the result buffer. But we may only care some of them. So I patched xcscope.el to add that functionality. There are 3 interactive functions added:

cscope-wash-flush
cscope-wash-keep
cscope-undo

Since it may not frequently used, I didn't assign hot keys for them.

The implementation is straight-forward: just make the buffer writable, them call flush-lines or keep-lines accordingly.

In fact, to gain more flexibility, you can just 'C-x C-q' to change *cscope* buffer to writable and operate on it directly.

[lgfang]

diff -cb xcscope.el xcscope.wash.el > xcscope.wash.patch

[lgfang]

Logged In: YES
user_id=1964982
Originator: YES

The patch file is based on the xcscope.el come with cscope-15.6.tar.gz