Adding topic create, list and remove

[bquenin]

Related to #288

Verification

$ ./swarm pull
$ ./swarm start
$ make test

Verification (CLI)

$ make install
$ amplifier &

$ amp topic ls
ID   Name   

$ amp topic create test1
2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d

$ amp topic create test1
2016/10/21 14:41:03 Failed to create topic: rpc error: code = 2 desc = Topic already exists: test1

$ amp topic create test2
11b11b55a457705e62ee678c681676316271e70cb5b9d25d8a781dbe17f82547

$ amp topic create test2
2016/10/21 14:41:08 Failed to create topic: rpc error: code = 2 desc = Topic already exists: test2

$ amp topic ls
ID                                                                 Name    
11b11b55a457705e62ee678c681676316271e70cb5b9d25d8a781dbe17f82547   test2   
2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d   test1   

$ amp topic rm 11b11b55a457705e62ee678c681676316271e70cb5b9d25d8a781dbe17f82547
11b11b55a457705e62ee678c681676316271e70cb5b9d25d8a781dbe17f82547

$ amp topic ls
ID                                                                 Name    
2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d   test1   

$ amp topic rm 2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d
2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d

$ amp topic ls
ID   Name   

$ amp topic rm 2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d
2016/10/21 14:41:14 Failed to remove topic: rpc error: code = 2 desc = Topic not found: 2106e15a3b1d132abcc6899f7ee7044235a73304f9770510ee2c396e609bbb3d

[subfuzion]

Fantastic! Please chat with @JosephGJ and @neha-viswanathan next week about getting the CLI test suite updated for this based on the test features that just landed here.