Changed HTTP URLs to HTTPS where possible (#270)

diff --git a/absl/algorithm/BUILD.bazel b/absl/algorithm/BUILD.bazel
index 4314ee8..8d266db 100644
--- a/absl/algorithm/BUILD.bazel
+++ b/absl/algorithm/BUILD.bazel
@@ -5,7 +5,7 @@
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
-#      http://www.apache.org/licenses/LICENSE-2.0
+#      https://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
diff --git a/absl/algorithm/CMakeLists.txt b/absl/algorithm/CMakeLists.txt
index 87a165c..c51eb10 100644
--- a/absl/algorithm/CMakeLists.txt
+++ b/absl/algorithm/CMakeLists.txt
@@ -5,7 +5,7 @@
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
-#      http://www.apache.org/licenses/LICENSE-2.0
+#      https://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
diff --git a/absl/algorithm/algorithm.h b/absl/algorithm/algorithm.h
index 3d65864..bb90215 100644
--- a/absl/algorithm/algorithm.h
+++ b/absl/algorithm/algorithm.h
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ -94,7 +94,7 @@
 // then the predicate is never invoked and the function returns false.
 //
 // This is a C++11-compatible implementation of C++14 `std::equal`.  See
-// http://en.cppreference.com/w/cpp/algorithm/equal for more information.
+// https://en.cppreference.com/w/cpp/algorithm/equal for more information.
 template <typename InputIter1, typename InputIter2, typename Pred>
 bool equal(InputIter1 first1, InputIter1 last1, InputIter2 first2,
            InputIter2 last2, Pred&& pred) {
diff --git a/absl/algorithm/algorithm_test.cc b/absl/algorithm/algorithm_test.cc
index e4322bc..81fccb6 100644
--- a/absl/algorithm/algorithm_test.cc
+++ b/absl/algorithm/algorithm_test.cc
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
diff --git a/absl/algorithm/container.h b/absl/algorithm/container.h
index 6d5f663..7348d63 100644
--- a/absl/algorithm/container.h
+++ b/absl/algorithm/container.h
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
diff --git a/absl/algorithm/container_test.cc b/absl/algorithm/container_test.cc
index 1502b17..04282b8 100644
--- a/absl/algorithm/container_test.cc
+++ b/absl/algorithm/container_test.cc
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
diff --git a/absl/algorithm/equal_benchmark.cc b/absl/algorithm/equal_benchmark.cc
index 19c0780..7bf62c9 100644
--- a/absl/algorithm/equal_benchmark.cc
+++ b/absl/algorithm/equal_benchmark.cc
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,