Add SASS variables for colors

assets/sass/app.sass

@@ -1,65 +1,3 @@
-$text-xlarge: 1.6em
-$text-large: 1.4em
-$text-medium: 1.2em
-$text-normal: 1.0em
-$text-small: 0.8em
-$text-tiny: 0.7em
-
-$dropdown-text-size: 0.9em
-$board-text-size: 0.9em
-
-$text-font: 'Helvetica Neue', Helvetica, Arial, sans-serif
-$text-color: #333
-
-$title-color: #333
-$page-title-size: 1.5em
-
-$link-color: #3366CC
-$link-color-focus: #DF5353
-$link-color-hover: #333
-
-$alert-default-text-color: #c09853
-$alert-default-background-color: #fcf8e3
-$alert-default-border-color: #fbeed5
-
-$alert-success-text-color: #468847
-$alert-success-background-color: #dff0d8
-$alert-success-border-color: #d6e9c6
-
-$alert-error-text-color: #b94a48
-$alert-error-background-color: #f2dede
-$alert-error-border-color: #eed3d7
-
-$alert-info-text-color: #3a87ad
-$alert-info-background-color: #d9edf7
-$alert-info-border-color: #bce8f1
-
-$alert-normal-text-color: #333
-$alert-normal-background-color: #f0f0f0
-$alert-normal-border-color: #ddd
-
-=appearance
-  -webkit-appearance: none
-  -moz-appearance: none
-
-=display-flex
-  display: -webkit-flex
-  display: flex
-
-=flex-direction($direction)
-  -webkit-flex-direction: $direction
-  flex-direction: $direction
-
-=flex-wrap
-  -webkit-flex-wrap: wrap
-  flex-wrap: wrap
-
-=align-content($position)
-  -webkit-align-items: $position
-  align-items: $position
-  -webkit-justify-content: $position
-  justify-content: $position
-
 @import reset
 @import base
 @import links