Switch to debian/compat = 9
Increase debhelper version.
Imported Upstream version 3.1.4
Merge tag 'upstream/3.1.4'

Upstream version 3.1.4
Added the octave-mpsolve package.
Added install file for octave-mpsolve.
Imported Upstream version 3.1.4
Merge tag 'upstream/3.1.4'

Upstream version 3.1.4
Imported Upstream version 3.1.4
Merge tag 'upstream/3.1.4'

Upstream version 3.1.4
Add support for multiarch.
Use {} in .install variables.
Added a new libmp3-dev.install
Make executable the file libmps3-dev.install
Corrected typo.
Possible hack.
Imported Upstream version 3.1.4
Merge tag 'upstream/3.1.4'

Upstream version 3.1.4
Fixed octave-mpsolve.install file.
Imported Upstream version 3.1.4