Update poison fang's description

Poison fang has 50% of poison, from this commit: https://github.com/Zarel/Pokemon-Showdown/commit/4839db60b31b376ac57284a26dd2ddea78fe946a
Merge pull request #1019 from Tempoanon/patch-10

Update poison fang's description
README: Improve links and intro

A slight reword of the intro, and a navigation bar above the intro to
quickly jump to the client repo or PS main.
Make sure that alts leave when a user is banned from a room
If a user is renamed, check if they are banned from their current rooms
Merge pull request #1021 from Slayer95/roomban

Fixes for room bans
Froslass is now banned from RU
http://www.smogon.com/forums/threads/np-ru-stage-1-dog-days-are-over-hello-kitty.3508302/page-10#post-5532624
Fix 3 move Jolteon/Raikou in Randbats

Removed hidden power grass from Jolteon and Raikou's movesets
Merge pull request #1022 from cometstorm/patch-4

Fix 3 move Jolteon/Raikou in Randbats
NEXT: Fix Aftermath

Update Aftermath to fix a bug involving it activating twice.
Merge pull request #1023 from NickMP/patch-2

NEXT: Fix Aftermath
Add /details command

Incorporates additional details into the data command
Merge pull request #1024 from SolarisFox/patch-1

Add /details command
RNG: Shield Dust

Shield Dust does not even permit rolls for secondary effects. This will
correct its interaction with the RNG.
Fix bug introduced in 529281272a807f06996666360ff82f8cda46c2de
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of https://github.com/jd4565/Pokemon-Showdown