Modernize the codebase

[Petross404]

This PR applies the default keywords to empty dtors, Q_DISABLE_COPY_MOVE macro to specifically delete any move or copy operation, const qualifies some variables and functions etc.

[arturbac]

I am not allowed to apply clang-format, so do it Yourself pls or let me push into PR.

[Petross404]

I am not allowed to apply clang-format, so do it Yourself pls or let me push into PR.

I am happy to help. Should I format the changed files only and run git commit --amend --no-edit?

[arturbac]

nvm Ill reformat code later.

[arturbac]

could You enable allow edit for me in PR, it is in Your options

[Petross404]

Like this?

[arturbac]

Like this?

sure thx.
Btw I do not like "pedantic" const correctness on everything, I never make errors "use after move" but it very often causes prevention of copy elision. Sometimes for complex code I use const when I explicitly want to know variable was not modified but not in such approach as in this PR, this is redundant and makes code less readable and possibly prevents copy elision for named variables if applicable.
Anyway it does nothing valuable in this code, but since You did that just make sure there is no such case when const named variable is returned from function and previously it was not const.

[Petross404]

Anyway it does nothing valuable in this code, but since You did that just make sure there is no such case when const named variable is returned from function and previously it was not const.

I suspect the compiler would rant about it? I might got carried away from clang-tidy's proposals and best practices. Whatever, I can remove them, it's not like it's the improvement or something.