Remove ZK paths suport names in vtctl commands

1. ZK path is resolved in methods tabletParamToTabletAlias,
   shardParamToKeyspaceShard and keyspaceParamsToKeyspace.
   Therefore, all of them are refactored to not accept ZK path
   and return error if do so.
2. Move vtPathToCell and keyspaceParamToKeyspace to
   vt/vtctl/plugin_zktopo.go since they contains zk
   logic only.
3. Remove resolveWildcards method in vtctl.go
4. Remove most zk stuff in command description
typofixes - https://github.com/vlajos/misspell_fixer
Merge branch 'typofixes-vlajos-20141204' of github.com:vlajos/vitess into vlajos-typofixes-vlajos-20141204
Merge branch 'vlajos-typofixes-vlajos-20141204'
Now using Context in Wrangler. Experimenting with Ping.
Also refactoring Validate commands to be simpler.
Merge branch 'master' into replication
Merge pull request #204 from yaoshengzhe/fix_remove_zk_vtctl

Remove ZK paths suport names in vtctl commands
Merge pull request #210 from youtube/replication

Replication
Change VitessInputFormat key type

Make VitessInputFormat emit <NullWritable, RowWritable> instead of
<KeyspaceIdWritable, RowWritable>