Fix a variety of mandoc nits
Only print once a bad abi during pkg update

Reported by:	tuxillo (#dragonflybsd on efnet)
Remove useless operator.

Dereferencing operator is useless in *ptr++ if result is unused,
hence remove confusing operator and type conversion.
Merge pull request #488 from grimreaper/master

Fix a variety of mdoc nits
Fix pkg create
Try to create db directory is MODE_WRITE is activated and it doesn't yet
exists
Fix .pkgconf handling
Implement pkg audit -q
For reinstallation of a package is the required dependencies has change.

Testing the list of dependency origin between installed and remote
allows us to catch default version of perl/postgresql/mysql/etc change.

Waiting for new solver that reduce number of manual user interaction
Avoid double copying while unpacking manifest.

libarchive allows zero-copy methods to unpack data by blocks, it
is useful thus to use archive_read_data_block instead of
archive_read_data as we perform sbuf copying anyway.
Fix dependency origin comparison commit
Remove the shlib options as the is now always used
Reinstall port in case the required shlibs has changed
Remove last shlib test in pkg check
make pkg install and pkg upgrade work again :)
Set user agent to pkg/PKGVERSION
Uses has to figure out manifest keys.
Fix gcc warnings
Remove dead code
Fix @cwd command handling in plist.

A line that was obtained by getline(3) call should not be considered
as permament storage, hence it is not a good idea to assign it to some
const char pointer. To fix this issue, convert prefix to static array
and copy getlined string to this static array to prevent package
corruption during plist parsing.