Update example configs, README.md and more

- Fix typos, remove misleading information, rephrase a few sentences
- Add info about hmac-<hash> hash types
- Remove <performance:maxwho> (the code which used this was removed in 96e4434 - @SaberUK)
- Change inspircd.github.org to inspircd.org
m_permchannels Construct the final line that will be saved in a std::string in WriteDatabase()
m_permchannels Save channel TS, topic set time and set by information

When loading, ignore and log channels with a name longer than Limits.MaxChan
m_permchannels Add the ability to save listmodes