More config for CreateCommand, add various methods

Adds multiple configurations to the command builder, and adds methods
to various structs.

Context::get_current_user is a shortcut to retrieve the current user
from the cache.

Message::get_member retrieves the member object of the message, if sent
in a guild. Message::is_private checks if the message was sent in a
Group or PrivateChannel.

User::member retrieves the user's member object in a guild by Id;

Adds 6 configurations to the command builder:

- dm_only: whether the command can only be used in direct messages;
- guild_only: whether the command can only be used in guilds;
- help_available: whether the command should be displayed in the help
  list;
- max_args: specify the maximum number of arguments a command must be
  given;
- min_args: specify the minimum number of arguments a command must be
  given;
- required_permissions: the permissions a member must have to be able
  to use the command;

1 files changed, 17 insertions, 6 deletions

diff --git a/src/model/user.rs b/src/model/user.rs
index adc766f..c249631 100644
--- a/src/model/user.rs
+++ b/src/model/user.rs
@@ -13,22 +13,24 @@ use ::internal::prelude::*;
 use ::utils::decode_array;
 use ::model::misc::Mentionable;
 
-#[cfg(feature = "methods")]
+#[cfg(feature="methods")]
 use serde_json::builder::ObjectBuilder;
 #[cfg(feature="methods")]
 use std::mem;
 #[cfg(feature = "methods")]
 use super::Message;
-#[cfg(feature = "methods")]
+#[cfg(all(feature = "cache", feature = "methods"))]
+use super::Member;
+#[cfg(feature="methods")]
 use time::Timespec;
-#[cfg(feature = "methods")]
+#[cfg(feature="methods")]
 use ::client::rest::{self, GuildPagination};
 #[cfg(feature="methods")]
 use super::GuildInfo;
 #[cfg(feature="methods")]
 use ::utils::builder::EditProfile;
 
-#[cfg(feature = "cache")]
+#[cfg(feature="cache")]
 use ::client::CACHE;
 
 impl CurrentUser {
@@ -59,7 +61,7 @@ impl CurrentUser {
     ///     .edit(|p| p
     ///         .avatar(Some(&avatar)));
     /// ```
-    #[cfg(feature = "methods")]
+    #[cfg(feature="methods")]
     pub fn edit<F>(&mut self, f: F) -> Result<()>
         where F: FnOnce(EditProfile) -> EditProfile {
         let mut map = ObjectBuilder::new()
@@ -102,8 +104,17 @@ impl User {
             format!(cdn!("/avatars/{}/{}.jpg"), self.id, av))
     }
 
+    /// Gets user as `Member` of a server.
+    #[cfg(all(feature="cache", feature="methods"))]
+    pub fn member<G>(&self, guild_id: G) -> Option<Member>
+        where G: Into<GuildId> {
+        let cache = CACHE.read().unwrap();
+
+        cache.get_member(guild_id.into(), self.id).cloned()
+    }
+
     /// Retrieves the time that this user was created at.
-    #[cfg(feature = "methods")]
+    #[cfg(feature="methods")]
     #[inline]
     pub fn created_at(&self) -> Timespec {
         self.id.created_at()