disable move operations on Timer

update library.properties

Revert "Simplify directory name in generated ZIP files"

This reverts commit a68b04d.

Use rvalue references and std::move to avoid copying Handler objects

move create_default() into a proper translation unit

remove 'const' which causes const iterator to be returned

add 'operator bool()' to Timer, to avoid peeking inside it

add noexcept specifications to all functions

improve formatting

Rename header to .hpp to ensure editors recognize it as C++

Reformat all C++ source files

Correct logic error in rescheduling functions

add rescheduling support