Allow restricted type aliasing during type inference

In 'Nat = inductive_'  We want to use the alias 'Nat' instead of the full
declaration during type inference. It is restricted aliasing because only
inductive type can be aliased that way.

Changes to be committed:
* GNUmakefile: tests don't run when using make all
* src/eval.ml: Call eval check for constructor before evaluating (Test - Nat Plus Work)
* src/lparse.ml:
	- Type inference: Allow restricted type aliasing
	- Type inference: Call now allow partial application
	- Type inference: Cons are typed as function
* src/lexer.ml: added (lex_str) and (sexp_parse_str)
* src/pexp.ml: removed useless declaration/include
* tests/eval_test.ml:
	- Mutually rec decl tests
	- Partial Application test

new file:
* tests/sexp_test.ml: test _*_ and _+_ precedence which both seems to be buggy