Add ImageMagick to setup scripts

Summary:
ImageMagick is needed to build out our topic icons. Though most devs won't need to do this (we
access the prod icons directly in dev_appserver), it's now technically a webapp dependency.

Test Plan: N/A

Reviewers: csilvers

Reviewed By: csilvers

Subscribers: mroth

Differential Revision: https://phabricator.khanacademy.org/D30783

linux-setup.sh

@@ -59,6 +59,7 @@ EOF
     # Needed to develop at Khan: git, python, node (js).
     # php is needed for phabricator
     # lib{freetype6{,-dev},{png,jpeg}-dev} are needed for PIL
+    # imagemagick is needed for image resizing and other operations
     # lib{xml2,xslt}-dev are needed for lxml
     # libyaml-dev is needed for pyyaml
     # libncurses-dev and libreadline-dev are needed for readline
@@ -67,6 +68,7 @@ EOF
         python-dev \
         pychecker python-mode python-setuptools python-pip python-virtualenv \
         libfreetype6 libfreetype6-dev libpng-dev libjpeg-dev \
+        imagemagick \
         libxslt1-dev \
         libyaml-dev \
         libncurses-dev libreadline-dev \
@@ -108,8 +110,7 @@ EOF
 
     # Not needed for Khan, but useful things to have.
     sudo apt-get install -y ntp abiword curl diffstat expect gimp \
-        imagemagick mplayer netcat netpbm screen w3m vim emacs \
-        google-chrome-stable
+        mplayer netcat netpbm screen w3m vim emacs google-chrome-stable
 
     # If you don't have the other ack installed, ack is shorter than ack-grep
     # This might fail if you already have ack installed, so let it fail silently.

mac-setup.sh

@@ -265,6 +265,16 @@ install_nginx() {
     fi
 }
 
+install_image_utils() {
+    info "Checking for imagemagick\n"
+    if ! brew ls imagemagick >/dev/null 2>&1; then
+        info "Installing imagemagick\n"
+        brew install imagemagick
+    else
+        success "imagemagick already installed"
+    fi
+}
+
 install_helpful_tools() {
     # This is useful for profiling
     # cf. http://www.khanacademy.org/r/fun-with-miniprofiler
@@ -312,6 +322,7 @@ update_git
 install_node
 install_phantomjs
 install_nginx
+install_image_utils
 install_helpful_tools
 
 notice "You might be done! \n\n \