blobserver/localdisk: fixed build problems on non-Windows

Change-Id: I5ec0fa71449d8802c8005bf802b334a385f5d257
Merge "blobserver/localdisk: fixed build problems on non-Windows"
index: add deletedAt method, and cache for deletion status

This method will be used to find out when a permanode or claim
was (un)deleted for the last time.

This change also introduces the keyDeletes index entry which
allows to find the permanodes/claims that a delete claim deletes.

Finally, since some index keys have changed, this CL introduces
a check for an index schema version, to force users to reindex
when needed.

http://camlistore.org/issue/191

Change-Id: I6f8e5d3030a6ddc8b21ff5dc5db311f2ea16f613
Merge "index: add deletedAt method, and cache for deletion status"
builder: add client side Basic Auth support.

Adds support for specifying additional masters to send results to.
The config file, named "builderbot-config", must be located in
osutil.CamliConfigDir(); on Unix, it will be under
$XDG_CONFIG_HOME/camlistore/, if XDG_CONFIG_HOME set, or
~/.config/camlistore/.  On Windows it will be under %APPDATA%\Camlistore\.
The expected format is one host per line, comments are not allowed and used
only for illustration below.  Some examples:

    # Post to default path on host1, no user auth.
    http://host1
    # Post to / on host2, no user auth.
    http://host2/
    # Post to /other/path on host3, no user auth.
    http://host3/other/path
    # Post to default path on host4, user 'user', password 'pass'.
    http://user:pass@host4
    # Post to / on host4 port 7070, user 'user', password 'pass'.
    http://user:pass@host4:7070/

This change also explicitly sets GOPATH to the copy of camlistore.org checked
out by the master before building the builder, and starting the build run.
This ensures we're not building against a random checkout of camlistore
pointed to by the user's environment.

The directory of the checked out source is moved from ${PWD}/camlistore.org
-> ${PWD}/src/camlistore.org so GOPATH can be set to $PWD and the requirement
of packages being under src/ is met.

Change-Id: I6e121c0aae9dae0c1832f782fa32619434ce9d2c
Merge "builder: add client side Basic Auth support."
third_party/goexif: fix shadowed err bug

Change-Id: Idf3c6669f7784958e24f82839cbe315492fbf24a
pkg/index: keyType keyPermanodeClaim for "claim" index entry

The index entry prefixed by "claim" had no keyType and
was always built "by hand" with pipes concatenation.
This change adds the documented keyPermanodeClaim to fix
that.

Change-Id: Ic59f7dbcccc6b223b155d5bffbf8e636209800cb
Merge "pkg/index: keyType keyPermanodeClaim for "claim" index entry"
search: query permanode attributes (a start)

Change-Id: I1e6109df0d09edf894a32934eec5be7b6ad9fc1c