kiji-schema: SCHEMA-544. Add support for protocol buffers

- Update table layout descriptors and CellSpec to support protobuf-encoded columns.
- Add simple unit-test.

issue: https://jira.kiji.org/browse/SCHEMA-544
review: https://review.kiji.org/r/1055
commit: https://github.com/kijiproject/kiji-schema/commit/3ae47da30d6b6b2b0e3a13a6e1e49080970cc344
kiji-express-examples: EXP-226. kiji-express-example depends on dead snapshot version of framework

issue: https://jira.kiji.org/browse/EXP-226
review: https://review.kiji.org/r/1183
commit: https://github.com/kijiproject/kiji-express-examples/commit/ccc3a878251cb15beee651900985466dd0d2443d
kiji-schema: SCHEMA-538.  Corrected KijiNotInstalledException error msgs

SCHEMA-538.  Corrected KijiNotInstalledException

New constructor uses reference to KijiURI instead of a String
representing only the instance name.

Retained legacy constructor and getInstanceName() method, but added new
constructor and getURI() method.

SCHEMA-538.  Corrected KijiNotInstalledException

Exception constructor was given full URI for uninstalled instance
instead of just the instance name.

KijiNotInstalledException stores full URI string

Previously, it contained a string containing only the name of the
uninstalled component, and whomever caught the exception had to add
"kiji://.env/" to the beginning of the error message.

KijiNotInstalledException retains legacy constructor

Updated KijiNotInstalledException such that the old constructor (which
took just an instance name as an argument) is still present, but marked
as @deprecated.

Replaced "String getURIName" with "KijiURI getURI"

Other minor changes based on feedback from Christophe (used
Preconditions instead of regular assert, fixed some javadoc formatting)

SCHEMA-538.  Javadoc and final cleanup.
commit: https://github.com/kijiproject/kiji-schema/commit/b18b55b6a5cd1cd9bc37c17e34a58e99b388855d
kiji-model-repository: KIJIREPO-34. Fix broken version of kiji-model-repository module.

issue: https://jira.kiji.org/browse/KIJIREPO-34
review: https://review.kiji.org/r/1184
commit: https://github.com/kijiproject/kiji-model-repository/commit/1baa5834c995a84409685bccbffc6717e4f86464