This commit implements multiple performance improvements
to the transaction code:
- Don't process xbps_pkg_name() N times each time we access
its package dictionary (via pkgdb or rpool), just do it once
at xbps_pkgdb_init() time. At pkgdb init time, it just creates
a property in pkgdb, "pkgname". At rpool time, each time a
package is accessed, the "pkgname" string property is added.
- The package transaction dictionary contains the "transaction"
object to know what's the pkg type. This has been changed to an
uint8, this simplifies the logic and it's faster than checking
a string object. See xbps_trans_type_t and xbps_transaction_pkg_type().
- Fixed the issue that was marked with XXX in transaction shlibs
checking code. This has been fixed and improved and resources are
now just freed as expected.
- Simplified random code all over the place, avoiding unnecessary
allocations or operations.
- Rename some transaction files to have a better description.
This is my first rototill to the code in 2020.
