several fixed links

most notably for aer and ignis

Author: omarcostahamido

start_here.ipynb

@@ -1,7 +1,6 @@
 {
  "cells": [
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    "cell_type": "markdown",
    "metadata": {},
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@@ -56,25 +55,25 @@
     "##  Aer\n",
     "\n",
     "Aer, the ‘air’ element, permeates all Qiskit elements. To really speed up development of quantum computers, we need better simulators with the ability to model realistic noise processes that occur during computation on actual devices. Aer provides a high-performance simulator framework for studying quantum computing algorithms and applications in the noisy intermediate-scale quantum regime. \n",
-    "1. [Aer provider](tutorials/aer/fundamentals/1_aer_provider.ipynb) - Gives a summary of the Qiskit Aer provider containing the Qasm, statevector, and unitary simulator.\n",
+    "1. [Aer provider](tutorials/aer/1_aer_provider.ipynb) - Gives a summary of the Qiskit Aer provider containing the Qasm, statevector, and unitary simulator.\n",
     "\n",
     "\n",
-    "2. [Device noise simulation](tutorials/aer/fundamentals/2_device_noise_simulation.ipynb) - Shows how to use the Qiskit Aer noise module to automatically generate a basic noise model for simulating hardware backends.\n",
+    "2. [Device noise simulation](tutorials/aer/2_device_noise_simulation.ipynb) - Shows how to use the Qiskit Aer noise module to automatically generate a basic noise model for simulating hardware backends.\n",
     "\n",
     "\n",
-    "3. [Building noise models](tutorials/aer/advanced/1_building_noise_models.ipynb) - Shows how to use Qiskit Aer noise module to construct custom noise models for noisy simulations\n",
+    "3. [Building noise models](tutorials/aer/3_building_noise_models.ipynb) - Shows how to use Qiskit Aer noise module to construct custom noise models for noisy simulations\n",
     "\n",
     "\n",
-    "4. [Custom gate noise](tutorials/aer/advanced/2_custom_gate_noise.ipynb) - Shows to implement simulations using custom noisy gates.\n",
+    "4. [Custom gate noise](tutorials/aer/4_custom_gate_noise.ipynb) - Shows to implement simulations using custom noisy gates.\n",
     "\n",
     "\n",
-    "5. [Noise transformations](tutorials/aer/advanced/3_noise_transformation.ipynb) - Noise approximation utility functions to construct approximate Clifford noise models out of a general noise model\n",
+    "5. [Noise transformations](tutorials/aer/5_noise_transformation.ipynb) - Noise approximation utility functions to construct approximate Clifford noise models out of a general noise model\n",
     "\n",
     "\n",
-    "6. [Extended stabilizer tutorial](tutorials/aer/advanced/4_extended_stabilizer_tutorial.ipynb) - Gives an overview of the *extended stabilizer* Qasm Simulator method\n",
+    "6. [Extended stabilizer tutorial](tutorials/aer/6_extended_stabilizer_tutorial.ipynb) - Gives an overview of the *extended stabilizer* Qasm Simulator method\n",
     "\n",
     "\n",
-    "7. [Matrix Product State simulator](tutorials/aer/advanced/5_matrix_product_state_method.ipynb) - Gives an overview of the *matrix product state* Simulator method\n",
+    "7. [Matrix Product State simulator](tutorials/aer/7_matrix_product_state_method.ipynb) - Gives an overview of the *matrix product state* Simulator method\n",
     "\n",
     "\n",
     "##  Ignis\n",
@@ -99,7 +98,7 @@
     "6. [Repetition Code](tutorials/ignis/6_repetition_code.ipynb) - How to run a simple error correction code, known as the repetition code. This can be used to characterize bit flip errors in the hardware.\n",
     "\n",
     "\n",
-    "7. [Accreditation](tutorials/ignis/7_repetition_code.ipynb) - protocol devised to characterize the reliability of noisy quantum devices.\n",
+    "7. [Accreditation](tutorials/ignis/7_accreditation.ipynb) - protocol devised to characterize the reliability of noisy quantum devices.\n",
     " \n",
     " \n",
     "##  Aqua\n",