Imported changes contributed by Robert Gyllenberg

[rafalcieslak]

This branch gathers the contributions provided by Robert Gyllenberg that were sent to me via e-mail in April 2016.

As Robert was working on sources from 1.0 release, this branch has diverged and will require careful merging.

Stuff that needs to be done before merging:

• Rebasing on top of master (in particular, dropping autotools).
• Re-applying pedantic fixes from master branch.
• Removing blame comments as they are unnecessary under version control.
• Cleaning up some redundant comments, maybe providing some extra docs.
• Unifying formatting of save/load routines.
• Investigating the design of new modules' UI.

This should be enough to ensure this branch fits perfectly.

[rafalcieslak]

This branch is expected to fix #17.

[rafalcieslak]

This is a duplicate of #19.