Major API/ABI cleanup bringing performance improvements and fixes.

These are the core interfaces in the new API:

rpool - Interface to interact with the repository pool.
rindex - Interface to interact with repository indexes.
pkgdb - Interface to interact with local packages.
transaction - Interface to interact with a transaction.

This also brings new repository index format, making the index file
per architecture and being incompatible with previous versions.

The transaction frequency flush option has been removed, and due to
the nature of package states it was causing more harm than good.

More changes coming soon, but the API shall remain stable from now on.

etc/xbps.conf

@@ -21,26 +21,15 @@
 # Enable syslog messages, set the value to false or 0 to disable.
 #Syslog = true
 
-# Number of packages to be processed in a transaction to trigger
-# a flush to the master package database. Set it to 0 to make it
-# only flush at required points.
-#
-#TransactionFrequencyFlush = 5
-
 # Repositories.
 #
 # You can specify here your list of repositories, the first
-# repository that contains a package will be used for most
-# targets in xbps-bin(8) and xbps-repo(8), with the exception
-# for updating on which all repositories will be looked at and
-# the newest version will be choosen.
+# repository matching a package expression will be used for most
+# targets in xbps-install(8) and xbps-query(8).
 #
 # Optionally a non default HTTP port can also be specified such as:
 # 	http://foo.local:8080/xbps-repo
 #
-# The order matters, and the top-most matching a package pattern
-# or name will be used.
-#
 # By default we use the official "public" repositories. You can add
 # your own repositories by specifying the path to the directory
 # where the plist index file (rindex.plist) is stored.