Update links in Readme.md (keon#411)

Fixed broken links to algorithms in `Readme.md`

README.md

@@ -75,10 +75,10 @@ If you want to uninstall algorithms, it is as simple as:
     - [n_sum](algorithms/arrays/n_sum.py)
 - [backtrack](algorithms/backtrack)
     - [general_solution.md](algorithms/backtrack/)
+    - [add_operators](algorithms/backtrack/add_operators.py)
     - [anagram](algorithms/backtrack/anagram.py)
     - [array_sum_combinations](algorithms/backtrack/array_sum_combinations.py)
     - [combination_sum](algorithms/backtrack/combination_sum.py)
-    - [expression_add_operators](algorithms/backtrack/expression_add_operators.py)
     - [factor_combinations](algorithms/backtrack/factor_combinations.py)
     - [generate_abbreviations](algorithms/backtrack/generate_abbreviations.py)
     - [generate_parenthesis](algorithms/backtrack/generate_parenthesis.py)
@@ -142,7 +142,7 @@ If you want to uninstall algorithms, it is as simple as:
     - [fibonacci](algorithms/dp/fib.py)
 - [graph](algorithms/graph)
     - [check_bipartite](algorithms/graph/check_bipartite.py)
-    - [strongly_connected](algorithms/graph/checkDiGraphStronglyConnected.py)
+    - [strongly_connected](algorithms/graph/check_digraph_strongly_connected.py)
     - [clone_graph](algorithms/graph/clone_graph.py)
     - [cycle_detection](algorithms/graph/cycle_detection.py)
     - [find_all_cliques](algorithms/graph/find_all_cliques.py)
@@ -221,8 +221,8 @@ If you want to uninstall algorithms, it is as simple as:
     - [zigzagiterator](algorithms/queues/zigzagiterator.py)
 - [search](algorithms/search)
     - [binary_search](algorithms/search/binary_search.py)
-    - [first_occurance](algorithms/search/first_occurance.py)
-    - [last_occurance](algorithms/search/last_occurance.py)
+    - [first_occurrence](algorithms/search/first_occurrence.py)
+    - [last_occurrence](algorithms/search/last_occurrence.py)
     - [linear_search](algorithms/search/linear_search.py)
     - [search_insert](algorithms/search/search_insert.py)
     - [two_sum](algorithms/search/two_sum.py)
@@ -269,7 +269,7 @@ If you want to uninstall algorithms, it is as simple as:
     - [is_sorted](algorithms/stack/is_sorted.py)
 - [strings](algorithms/strings)
     - [fizzbuzz](algorithms/strings/fizzbuzz.py)
-    - [delete_reoccurring_characters](algorithms/strings/delete_reoccurring_characters.py)
+    - [delete_reoccurring](algorithms/strings/delete_reoccurring.py)
     - [strip_url_params](algorithms/strings/strip_url_params.py)
     - [validate_coordinates](algorithms/strings/validate_coordinates.py)
     - [domain_extractor](algorithms/strings/domain_extractor.py)
@@ -304,8 +304,8 @@ If you want to uninstall algorithms, it is as simple as:
     - [first_unique_char](algorithms/strings/first_unique_char.py)
     - [repeat_substring](algorithms/strings/repeat_substring.py)     
 - [tree](algorithms/tree)
-    - [bst](algorithms/tree/tree/bst)
-        - [array2bst](algorithms/tree/bst/array2bst.py)
+    - [bst](algorithms/tree/bst)
+        - [array_to_bst](algorithms/tree/bst/array_to_bst.py)
         - [bst_closest_value](algorithms/tree/bst/bst_closest_value.py)
         - [BSTIterator](algorithms/tree/bst/BSTIterator.py)
         - [delete_node](algorithms/tree/bst/delete_node.py)
@@ -334,7 +334,7 @@ If you want to uninstall algorithms, it is as simple as:
         - [add_and_search](algorithms/tree/trie/add_and_search.py)
         - [trie](algorithms/tree/trie/trie.py)
     - [binary_tree_paths](algorithms/tree/binary_tree_paths.py)
-    - [bintree2list](algorithms/tree/bintree2list.py)
+    - [bin_tree_to_list](algorithms/tree/bin_tree_to_list.py)
     - [deepest_left](algorithms/tree/deepest_left.py)
     - [invert_tree](algorithms/tree/invert_tree.py)
     - [is_balanced](algorithms/tree/is_balanced.py)