Paginate rest::get_guilds and add helper methods

Paginate the rest::get_guilds endpoint, which can be used to retrieve
the guilds after-or-before a certain guild's Id, with a limit of results
to return (100 is the max).

Example usage:

```rs
use serenity::client::rest::GuildPagination;

let target = GuildPagination::After(GuildId(81384788765712384));

let guilds = context.get_guilds(target, 50);
```

Additionally, add a method of `CurrentUser::guilds()`, to retrieve the
current user's guilds. A limit of 100 is set, as (most) users can not be
in more than 100 guilds.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/model/user.rs b/src/model/user.rs
index d7ea416..88a6f9d 100644
--- a/src/model/user.rs
+++ b/src/model/user.rs
@@ -5,11 +5,13 @@ use super::{
     FriendSourceFlags,
     GuildContainer,
     GuildId,
+    GuildInfo,
     Mention,
     RoleId,
     UserSettings,
     User,
 };
+use ::client::rest::GuildPagination;
 use ::internal::prelude::*;
 use ::utils::decode_array;
 
@@ -31,6 +33,11 @@ impl CurrentUser {
         self.avatar.as_ref().map(|av|
             format!(cdn!("/avatars/{}/{}.jpg"), self.id, av))
     }
+
+    /// Gets a list of guilds that the current user is in.
+    pub fn guilds(&self) -> Result<Vec<GuildInfo>> {
+        rest::get_guilds(GuildPagination::After(GuildId(0)), 100)
+    }
 }
 
 impl User {