Update whatsnew doc section

Author: bgoujaud

docs/source/whatsnew/0.1.0.rst

@@ -1,24 +1,45 @@
 What's new in PEPit 0.1.0
 =========================
 
-- The method ``add_constraint`` has been added to the class ``PEP`` for general constraints not necessarily related to a specific function.
-For readability of your code,
-we suggest to use the method ``set_initial_condition`` when the constraint is the initial one,
-and the method ``add_constraint`` for any other constraint.
+- Adding general constraints to your problem.
 
-- CVXPY solver options can be provided to the method ``PEP.solve``.
+    | The method ``add_constraint`` has been added to the class ``PEP`` for general constraints not necessarily related to a specific function.
+    | For readability of your code,
+      we suggest to use the method ``set_initial_condition`` when the constraint is the initial one,
+      and the method ``add_constraint`` for any other constraint.
 
-- The `tracetrick` option of the method ``PEP.solve`` has been replaced by `dimension_reduction_heuristic`.
-Set to None by default, this option can be set to "trace" or "logdet{followed by a number}" to use one of those heuristic.
+- Adding LMI constraints to your problem.
 
-- The verbose mode of the method ``PEP.solve`` and of the provided examples files are now integers, allowing a bigger granularity.
+    The method ``add_psd_matrix`` has been added to the class ``PEP`` and must be used to add LMI constraints to your problem.
 
-- The parameters that characterize a function class must be provided directly as arguments of this function class, not through the dict "param" anymore.
-Example: `PEP.declare_function(function_class=SmoothStronglyConvexFunction, mu=.1, L=1.)`
+- CVXPY options.
 
-- ``null_point`` and ``null_expression`` have been added to the module ``PEPit`` to facilitate the access to a ``Point`` or an ``Expression`` initialized to 0.
+    | PEPit uses CVXPY to solve the underlying SDP of your problem.
+    | CVXPY solver options can be provided to the method ``PEP.solve``.
+
+- Optimizing dimension of the solution.
+
+    | The ``tracetrick`` option of the method ``PEP.solve`` has been replaced by ``dimension_reduction_heuristic``.
+    | Set to None by default, this option can be set to "`trace`" or "`logdet{followed by a number}`" to use one of those heuristic.
+
+- Granularity of the verbose mode has evolved.
+
+    | The verbose mode of the method ``PEP.solve`` and of the provided examples files are now integers:
+        - 0: No verbose at all
+        - 1: PEPit information is printed but not CVXPY's
+        - 2: Both PEPit and CVXPY details are printed
+
+- Parameters of function classes.
+
+    | The parameters that characterize a function class must be provided directly as arguments of this function class, not through the dict "param" anymore.
+    | Example: ``PEP.declare_function(function_class=SmoothStronglyConvexFunction, mu=.1, L=1.)``
+
+- Initializing a Point or an Expression to 0.
+
+    ``null_point`` and ``null_expression`` have been added to the module ``PEPit`` to facilitate the access to a ``Point`` or an ``Expression`` initialized to 0.
 
 - 3 new function classes have been added:
+
     - ``ConvexSupportFunction`` for convex support functions (see [1])
     - ``ConvexQGFunction``, for convex and quadratically upper bounded functions (see [2])
     - ``RsiEbFunction``, for functions verifying lower restricted secant inequality and upper error bound (see [3])