v2 reverted to using `emacsql-sqlite` instead of `emacsql-sqlite3`. It
will now try to build the needed `sqlite3` executable by itself, using a
C compiler that it can find, which is normally gcc or clang.
Previously in v1 it would only check for `sqlite3` executable (using
`executable-find`) and wouldn't do anything else.
- Added platform-dependent checks for some of the executables needed for
org-download-clipboard to work.
- Fixed a typo in one of the error messages for org-roam.
