Update README.md

Author: dankmolot

README.md

@@ -1,2 +1,75 @@
 # gm_pgsqloo
 PostgreSQL binary module for Garry's Mod
+
+## Example
+```lua
+require "pgsqloo"
+
+local db = pgsqloo.Connection("postgresql://postgres@localhost/postgres?application_name=pgsqloo")
+
+function db:OnConnected(err)
+    if err then
+        print("Failed to connect to database:", err)
+    else
+        print("Successfully connected to database")
+    end
+end
+
+db:Connect()
+
+db:Query("SELECT * FROM users", function(err, result)
+    if err then
+        print("Failed to get all users:", err)
+    else
+        print("Users:")
+        PrintTable(result)
+    end
+end)
+
+local task = db:Query("SELECT * FROM stats WHERE level = $1 AND money > $2", {80, 99999}):Wait()
+if task:IsSuccess() then
+    PrintTable(task:GetResult())
+else
+    print(task:GetError())
+end
+```
+
+## API
+### Global API
+```lua
+-- See https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING
+pgsqloo.Connection(url: string) -> PostgreConnection
+```
+### PostgreConnection
+```lua
+PostgreConnection:Connect() -> PostgreTask<nil>
+PostgreConnection:Query(sql: string, args: table?, callback: function(err: string?, result: Result?)?) -> PostgreTask<Result>
+PostgreConnection:PreparedQuery(name: string, args: table?, callback: function(err: string?, result: Result?)?) -> PostgreTask<Result>
+PostgreConnection:Prepare(name: string, sql: string)
+PostgreConnection:Unprepare(name: string)
+PostgreConnection:Disconnect(wait: bool = false)
+PostgreConnection:IsConnected() -> bool
+PostgreConnection:IsConnecting() -> bool
+PostgreConnection:Database() -> string
+PostgreConnection:Username() -> string
+PostgreConnection:Hostname() -> string
+PostgreConnection:Port() -> string
+PostgreConnection:BackendPID() -> number
+PostgreConnection:ProtocolVersion() -> number
+PostgreConnection:ServerVersion() -> number
+PostgreConnection:GetClientEncoding() -> string
+PostgreConnection:SetClientEncoding(encoding: string)
+PostgreConnection:EncodingID() -> number
+
+-- Events
+PostgreConnection.OnConnected(conn: PostgreConnection, err: string?)
+```
+### PostgreTask
+```lua
+PostgreTask:Wait() -> PostgreTask
+PostgreTask:IsSuccess() -> bool
+PostgreTask:IsError() -> bool
+PostgreTask:IsProcessing() -> bool
+PostgreTask:GetResult() -> ResultType/nil
+PostgreTask:GetError() -> string/nil
+```