Tmux 2.0 on OSX: ~/.tmux.conf doesn’t work

I've installed tmux 2.0 from homebrew on OSX 10.10.5
By default it does not create a config, but I've researched that there should be ~/.tmux.conf file so I've created it myself
I'm using iTerm2.

The problem is that whatever I add to this config file – it doesn't affect tmux. So after restarting tmux I see no changes…

I want my tmux to have large scrollback buffer:

set -g history-limit 65000

No result((

I want to install this awesome tmux-powerline but after folowing the instructions preciesly I see no changes – just standard tmux line instead of that nice customized one((
I've tried even powerline project and it works with Vim and prompt line, but totally ignores my Tmux line…

my ~/.tmux.conf:

### enable mouse: ###
set -g mode-mouse on

### Scrollback buffer ###
set -g history-limit 65000

### Powerline path: ###
#source /usr/local/lib/python2.7/site-packages/powerline/bindings/tmux/powerline.conf

### 256 colour support
#set -g default-terminal "xterm"
set -g default-terminal "screen-256color"

### TMUX-Powerline ###
set-option -g status on
set-option -g status-interval 2
set-option -g status-utf8 on
set-option -g status-justify "centre"
set-option -g status-left-length 60
set-option -g status-right-length 90
set-option -g status-left "#(~/scripts/tmux-powerline/powerline.sh left)"
set-option -g status-right "#(~/scripts/tmux-powerline/powerline.sh right)"

set-window-option -g window-status-current-format "#[fg=colour235, bg=colour27]⮀#[fg=colour255, bg=colour27] #I ⮁ #W #[fg=colour27, bg=colour235]⮀"

Please help me to determine what's the problem with my tmux or it's config file.
Thank you