Kruskal files added

Will move development to new branch (should have done that from the start).
Things compile and run ok but the animation code is Prim's and the
algorithm is currently not deployed so it shouldn't break anything the dev
branch.

Author: lee-naish

src/algorithms/controllers/README_graph_search

@@ -39,3 +39,8 @@ dijkstra.js has been moved in the right direction wrt the points above
 and AStar.js is a copied and edited version (might have been better to
 generalise some code and use a file with common code).
 
+The new version of prim.js is based on dijkstra.js (same algorithm
+structure but computes MST instead of shortest paths) and kruskal is based
+on prim.js (different algorithm structure so they are quite different
+but both compute MST).
+

src/algorithms/controllers/index.js

@@ -3,8 +3,6 @@ export { default as binaryTreeInsertion } from './binaryTreeInsertion';
 export { default as heapSort } from './heapSort';
 export { default as quickSort } from './quickSort';
 export { default as quickSortM3 } from './quickSortM3';
-export { default as prim_old } from './prim_old';
-export { default as prim } from './prim';
 export { default as transitiveClosure } from './transitiveClosure';
 export { default as bruteForceStringSearch } from './bruteForceStringSearch';
 export { default as horspoolStringSearch } from './horspoolStringSearch';
@@ -17,3 +15,6 @@ export { default as AStar } from './AStar';
 export { default as BFS } from './BFS';
 export { default as DFS } from './DFS';
 export { default as DFSrec } from './DFSrec';
+export { default as prim_old } from './prim_old';
+export { default as prim } from './prim';
+export { default as kruskal } from './kruskal';