Structure for 3D Cartesian Grid created.

Unification of boundary conditions into one file.

Some changes to input file for reference cases. This should have been
done in another branch but I wanto to commit to save progress and I
don't want to deal with tswitching branches right now, I'm very busy
watching Futurama.

src/modules/mesh/moduleMesh.f90

@@ -68,13 +68,15 @@ MODULE moduleMesh
     !Physical surface for the edge
     INTEGER:: physicalSurface
     CONTAINS
-      PROCEDURE(initEdge_interface),     DEFERRED, PASS:: init
-      PROCEDURE(getNodesEdge_interface), DEFERRED, PASS:: getNodes
-      PROCEDURE(randPosEdge_interface),  DEFERRED, PASS:: randPos
+      PROCEDURE(initEdge_interface),         DEFERRED, PASS:: init
+      PROCEDURE(getNodesEdge_interface),     DEFERRED, PASS:: getNodes
+      PROCEDURE(intersectionEdge_interface), DEFERRED, PASS:: intersection
+      PROCEDURE(randPosEdge_interface),      DEFERRED, PASS:: randPos
 
   END TYPE meshEdge
 
   ABSTRACT INTERFACE
+    !Inits the edge parameters
     SUBROUTINE initEdge_interface(self, n, p, bt, physicalSurface)
       IMPORT:: meshEdge
 
@@ -86,13 +88,24 @@ MODULE moduleMesh
 
     END SUBROUTINE initEdge_interface
 
+    !Get nodes index from node
     PURE FUNCTION getNodesEdge_interface(self) RESULT(n)
       IMPORT:: meshEdge
       CLASS(meshEdge), INTENT(in):: self
       INTEGER, ALLOCATABLE:: n(:)
 
-    END FUNCTION
+    END FUNCTION getNodesEdge_interface
 
+    !Returns the intersecction between an edge and a line defined by point r0 and vector v0
+    PURE FUNCTION intersectionEdge_interface(self, r0, v0) RESULT(r)
+      IMPORT:: meshEdge
+      CLASS(meshEdge), INTENT(in):: self
+      REAL(8), INTENT(in), DIMENSION(1:3):: r0, v0
+      REAL(8):: r(1:3)
+
+    END FUNCTION intersectionEdge_interface
+
+    !Returns a random position in the edge
     FUNCTION randPosEdge_interface(self) RESULT(r)
       IMPORT:: meshEdge
       CLASS(meshEdge), INTENT(in):: self
@@ -391,11 +404,8 @@ MODULE moduleMesh
       IMPLICIT NONE
 
       CLASS(meshVol), INTENT(inout):: self
-      INTEGER:: modCollisions !Remain of current iteration and everyCollisions
-      INTEGER:: iterToCollisions !Number of iterations from current to next collision
       INTEGER:: nPart !Number of particles inside the cell
       REAL(8):: pMax !Maximum probability of collision
-      INTEGER:: nCollIter !Number of collisions to be computed in this iteration
       INTEGER:: rnd !random index
       TYPE(particle), POINTER:: part_i, part_j
       INTEGER:: n !collision