[doc] Update Changelog for 1.1

doc/ChangeLog.md

@@ -2,6 +2,39 @@
 
 # Changelog
 
+## Version 1.1.0
+
+This is Version 1.1.0 of Itertools, a single-header library for adapting C++ ranges.
+
+We thank all contributors: Daniel Bauernfeind, Alexander Hampel, Dylan Simon, Nils Wentzell
+
+Find below an itemized list of changes in this release.
+
+### General
+* Bugfix: Use sentinel_t for those range adaptors using std::end/cend on the underlying range
+* Add defaulted operator== to the various range adaptors
+* Fix make_vector_from_range to work for ranges with mismatching begin and end type
+* Add benchmarks for range and product_range
+* Important FIX in range implementation for nontrivial steps + test
+* Be sure to add initializer for all member of range type
+* Keep alias range::index_t for backward compatibility
+* Add range::all_t and associated static member range::all
+* Merge range implementation of nda, improve range() documentability
+* Make sure to generate empty ranges in accordance with python ranges
+
+### doc
+* Add link to reference doc to README.md
+* Minor doc cleanups for doxygen generation, add Doxyfile and update .gitignore
+
+### c++20
+* Resplace std::result_of by std::invoke_result
+
+### cmake
+* Bump Version number to 1.1.0
+* Set CXX standard using target_compile_features
+* Remove unused FindPython.cmake file
+
+
 ## Version 1.0.0
 
 Itertools Version 1.0.0 is a single-header