Small changes for clang compatibility

I have made some minor changes (mostly to space.c) so that the code now compiles out of the box with the clang compiler.

The main change is the removal of nested functions in space.c. They have been replaced by static functions.

Added 1 commit:

• 37e23cc0 - Updated the install instructions to specify compiler brands and versions that have been tested.

Added 1 commit:

• 715f950e - Added two missing headers that raised warning messages with the Intel compiler.

Status changed to merged

mentioned in commit 2dc8a2e7