add debug.dump-namespace command

[aryairani]

The debug.dump-namespace command dumps everything in the root namespace and recursive history to stdout as text (no patch contents yet, or definitions).

Controversial decision?
It uses traceM to print each individual namespace instead of generating an IO Pretty in OutputMessages like normal, because it was crashing when I did that. Possibly due to the Pretty being too big? That implementation is still here though.
I guess I don't care too much since it's a debug.<...> command.

Loose ends:
The things that are References are displayed with #, but the things that are just hashes (namespaces and patches) don't.

Sample output:

Namespace agu597jbfndk724etrdcd6r7u3b1ua7cvtk3n70dk3qtv6psfhldofrq8d2v7nbjdb56vfbk7vuentmjepqvg0i8phlha3u5k4sep7o
  Causal Parents:
    7asfbtqmoj56pq7b053v2jc1spgb8g5j4cg1tj97ausi3scveqa50ktv4b2ofoclnkqmnl18vnt5d83jrh85qd43nnrsh6qetbksb70
  Children:
    _base jh8ecig8at8tehvcgt3n2rjd1lf90s0pl9tsu18n30233h0ks9tkf1r3kjvbg49ide03ngso618k7lpm19t2h9818eefqau730rugkg
Namespace jh8ecig8at8tehvcgt3n2rjd1lf90s0pl9tsu18n30233h0ks9tkf1r3kjvbg49ide03ngso618k7lpm19t2h9818eefqau730rugkg
  Causal Parents:
    ug7grqhdmdl1n2cgsq3oppc4p68joqrmi050fr5a8oo25bmhv95t8sptov04mmv6l39stbgf3dgiae8sdc1q2gbugkco37licb5suu0
  Children:
    releases q7v595v9tbh0qs3t5ocl6vo2b3it9oenptu7kqgr4tdpmopfl6d2joelg2tga2vb3dcpvdlhdg98j0bc7t73ceefvchvksv5gmbdni0
    series   7ip67a0f1vn1n4vfujrh2veam7qrp6nfaa43hbvopsaoe841or0pitnn8ebbcqq2cpisd9nnc1r4sqligr53aqh22q7ed3rkb8iij68
    trunk    1fd5tlm9hq4n6qror5dch6kgj0kk1uoe42u65pe9v264fpm9jff228l3u3j0adgh6jivu6upti4b9piueraf7j8ufopbml7mkcm1qfo
Namespace q7v595v9tbh0qs3t5ocl6vo2b3it9oenptu7kqgr4tdpmopfl6d2joelg2tga2vb3dcpvdlhdg98j0bc7t73ceefvchvksv5gmbdni0
  Causal Parents:
    7ip67a0f1vn1n4vfujrh2veam7qrp6nfaa43hbvopsaoe841or0pitnn8ebbcqq2cpisd9nnc1r4sqligr53aqh22q7ed3rkb8iij68
  Children:
    _M1m    atln3qt5l34gpugulg1rjv6v318fl8h1g5a3dn7vl09qkn9v5bbpspumhlbl4j4h6n1ilp12lj0h80hd60q1lpj6iti977sn9s4qs7g
    _latest atln3qt5l34gpugulg1rjv6v318fl8h1g5a3dn7vl09qkn9v5bbpspumhlbl4j4h6n1ilp12lj0h80hd60q1lpj6iti977sn9s4qs7g
Namespace atln3qt5l34gpugulg1rjv6v318fl8h1g5a3dn7vl09qkn9v5bbpspumhlbl4j4h6n1ilp12lj0h80hd60q1lpj6iti977sn9s4qs7g
  Causal Parents:
    7asfbtqmoj56pq7b053v2jc1spgb8g5j4cg1tj97ausi3scveqa50ktv4b2ofoclnkqmnl18vnt5d83jrh85qd43nnrsh6qetbksb70
  Terms:
    bug
      ##bug
    todo
      ##todo
    <unnamed>
      #036dh126aoj6teannro7i689shik9k1nppm9d3img9rj5ub3ea0ee8on12haj7og4pquqncau85qjci0q7qpqelai8i5tbep25at6cg
      + #uqdd5t2fgn50t7f7s8n60k7qqp6s9uqce93uhtuam0i0bks0o9pdt8p6cj4qrbusq15vkqvfq8dooecmclp3r7s2k7krthk9etotqe8
    <unnamed>
      #0fbpmk2kq5udttfrn3fm07pn8s0hl030b1iht1umfcon9vihlptctfkcj5kunhli8igboh45bt8qlfnti526lju08mlkb48vdhj580g
      + #uqdd5t2fgn50t7f7s8n60k7qqp6s9uqce93uhtuam0i0bks0o9pdt8p6cj4qrbusq15vkqvfq8dooecmclp3r7s2k7krthk9etotqe8
    .
      #0hoa6tis7604fo17o91lfjflsvd843uvm7sueu5rfqqn5nbneajoh9fldfbmmjnhh1h2690ktfflrbb96q9lksesuh3t5amcc1ph92g
    <unnamed>
      #0i631k5do46t9fo6h315660j15qt8bh9b6v6qe721afo7eqjoa9vppou6mpetpbiu6s7s2s0heorncu08s60hmhifeikhngd8k9dloo
      + #uqdd5t2fgn50t7f7s8n60k7qqp6s9uqce93uhtuam0i0bks0o9pdt8p6cj4qrbusq15vkqvfq8dooecmclp3r7s2k7krthk9etotqe8
    <unnamed>
      #0kfc43voktd0n5lpogsd16al987qjbkusca0mgr2b2n8e0b4962s7cqpfd1b0ihhapja4sv0444s0gph8t8n0en6rfaqaltbnbmkum8.0c3
      + #uqdd5t2fgn50t7f7s8n60k7qqp6s9uqce93uhtuam0i0bks0o9pdt8p6cj4qrbusq15vkqvfq8dooecmclp3r7s2k7krthk9etotqe8
...