message: Just const decorating some functions
diff: @@ -317,14 +317,14 @@ public:
  * \return Returns maximum number of items that can be stored in this Bucket instance.
  *
  */
  - int get_capacity() { return m_capacity; }
  + int get_capacity() const { return m_capacity; }
  /*!
  * \brief Returns current number of items in this Bucket instance.
  *
  * \return Returns current number of items in this Bucket instance.
  */
  - int get_size() { return m_size; }
  + int get_size() const { return m_size; }
  ///@}
  axom_map::Node<Key, T>* m_list;
  @@ -601,23 +601,23 @@ public:
  *
  * \return A pointer to the queried bucket.
  */
  - std::size_t bucket(std::size_t hash) { return hash % m_bucket_count; }
  + std::size_t bucket(std::size_t hash) const { return hash % m_bucket_count; }
  /*!
  * \brief Returns the maximum number of items per bucket.
  * \return bucket_len the maximum number of items per bucket.
  */
  - int bucket_size() { return m_bucket_len; }
  + int bucket_size() const { return m_bucket_len; }
  /*!
  * \brief Returns the number of buckets in the Map.
  * \return bucket_count
  */
  - int bucket_count() { return m_bucket_count; }
  + int bucket_count() const { return m_bucket_count; }
  /*!
  * \brief Returns the amount of items in the Map instance.
  * \return size the amount of items in the Map instance.
  */
  - int size() { return m_size; }
  + int size() const { return m_size; }
  /*!
  * \brief Returns the overall capacity of the Map instance.
  * \return capacity the overall capacity of the Map instance.
  @@ -633,14 +633,14 @@ public:
  * return results of other Map functions.
  * \return m_end the values of the sentinel node for failure checks
  */
  - const axom_map::Node<Key,T> &end() { return m_end; }
  + const axom_map::Node<Key,T> &end() const { return m_end; }
  /*!
  * \brief Returns maximum load factor (ratio between size and bucket count)
  * hash table will reach before check_rehash() returns true.
  *
  * \return max_load_factor maximum load factor desired for this hash table. Default 1.0
  */
  - float max_load_factor() { return m_load_factor; }
  + float max_load_factor() const { return m_load_factor; }
  /*!
  * \brief Sets maximum load factor (ratio between size and bucket count)
  * hash table will reach before check_rehash returns true. Default value is
  @@ -654,7 +654,7 @@ public:
  *
  * \return load_factor the ratio between the amount of items in the Map and the amount of buckets.
  */
  - float load_factor() { return m_size/m_bucket_count; }
  + float load_factor() const { return m_size/m_bucket_count; }
  /*!
  * \brief Returns whether a rehash is necessary for this Map instance. Does so based on two metrics. The
  