Update API so that the worker_t parameter is given on creating the sync bloc.

(API breakage), more RAII like.

doc/API.txt

@@ -1,10 +1,11 @@
-Evolution of the API
---------------------
+API incompatibility
+-------------------
 
 V0.1.*: * First formal version of API
 
-V0.2.*: * worker_sync takes a 'worker_t' as an additional parameter
-	(This allows to perform a wait-on-event instead of a busy waiting). 
+V0.2.*: * worker_start takes a 'worker_t' as an additional parameter
+	(This allows to perform a wait-on-event instead of a busy waiting).
+        * worker_spawn doesn't take into a 'worker_t' anymore.
 	* worker_init takes an int as numWorker instead of an unsingned int.
 	* RBTREE pop method has been renamed into _pop_at
         * SNAPSHOT_DEF has been removed. use SNAPSHOT_SPSC_DEF
@@ -12,12 +13,12 @@ V0.2.*: * worker_sync takes a 'worker_t' as an additional parameter
         The interface is similar to dict _get_at, making the API cleaner
         and more generic.
             _set_at2(a,i,x) ==> set(*_get_at(a,i),x)
-        * DICT SET _set_at method has been renamed as _push
+        * Rename DICT SET _set_at method as _push
         Since there is no key, it is a push method, not a _set_at method.
-        * DICT_SET_DEF2 ==> DICT_SET_DEF
+        * Rename DICT_SET_DEF2 as DICT_SET_DEF
         since it only requires one argument.
-        * ALGO _contains ==> _contain_p
+        * Rename ALGO _contains as _contain_p
         since it is a predicate '_p' and it shall be in infinitive form.
-        * Rename algo _map into _for_each (Standard name).
+        * Rename algo _map as _for_each (Standard name).