Bugfix for memory size computations/Embedded printf

- Fixed a bug in computation of the heap size via updates of the `__memory_size` variable.
- Added a test case for the above (e-acsl-runtime/memsize.c).
- Added embedded printf to the C memory model. This removes functionality from stdio.h and assert.h headers.
- Small updates and stylistic issues in the C code of the memory model.

See merge request !21

Replaced system-wide assertions with custom assertions using embedded
printf library

consistent with the rest of the C files

since the latter is faster

they are more generic and not exposed to the global scope

so they are restricted to e_acsl_mmodel.c compile unit

(__memory_size)  is computed correctly

tracked heap memory to be computed incorrectly for the following cases:
    - realloc is supplied 0
    - realloc fails

[Makefile] fix installation with non-standard prefix

Create `BINDIR` directory if necessary before copying file into it.

See merge request !23

better handling of \valid on pointers to empty structs in Value

Adapt to branch feature/boris/valid-function-predicate



See merge request !20

Feature/annotate assembly

Branch compatible with Frama-C branch of the same name (MR 486).

See merge request !22