* orm: add tracing of the generated queries by the orm module, when a program is compiled with `-d trace_orm`
* examples: fix examples/database/orm.v, add comments, and ensure that the example can be run several times with no errors
The example demonstrates connecting to all 3 DBs in the same program, and will be added to the CI very soon,
to serve both as a regression test, if it fails, and as an example to how to use the ORM in combination with
raw SQL queries to the DBs (which are driver/wrapper specific, unlike the ORM, but can be more convenient in some situations).
* add mysql to orm
* fix got to big packet error
* format sql.v
* format example
* custom sql types
* add mysql table cration
* add documentation
* format sql.v
* fix markdown
* start implementing select_expr for mysql
* remove orm.c
* format sql.v
* finish mysql expr
* remove c
* remove unessecary files
* change to c implementation
* remove c
* added str interpolation for idents
* fix string insert
* fix compilation problems
* fix gitly compilation
* fix typing mistake
* add link to orm docs
