GMP change may affect eigen3

[Steve M. Robbins]

Hello,

This message is addressed to all maintainers of a package that
build-depends on gmp.

Yesterday's upload (gmp version 5.1.2+dfsg-2) changed the location of
gmp.h from /usr/include to /usr/include/$(multi-arch-triplet).  This
was done to fix bug #675577.  This change *should* be invisible, since
the compiler searches by default /usr/include/$(multi-arch-triplet).
I tested a few packages and found they built fine.  However, I've been
informed of one package that does fail to build with this change.
Since there may be other such packages, I thought I'd send out this
note to alert everyone.

Secondly: I removed the libtool .la files.  They had been 'emptied'
since 2011, so hopefully this causes no issue. 

Regards,
-Steve