Implement missing pieces for cancel build

We allow to cancel only created builds at this point.

assets/scripts/app/app.coffee

@@ -22,6 +22,9 @@ unless window.TravisApplication
     lookup: ->
       @__container__.lookup.apply @__container__, arguments
 
+    flash: (options) ->
+      Travis.lookup('controller:flash').loadFlashes([options])
+
     storeAfterSignInPath: (path) ->
       @get('auth').storeAfterSignInPath(path)
 

assets/scripts/app/models/build.coffee

@@ -62,11 +62,11 @@ require 'travis/model'
   ).property('rawConfigKeys.length')
 
   canCancel: (->
-    @get('state') == 'created' # TODO
-  ).property('state')
+    !@get('isFinished') && @get('jobs').filter( (j) -> j.get('canCancel') ).get('length') > 0
+  ).property('isFinished', 'jobs.@each.canCancel')
 
   cancel: (->
-    Travis.ajax.post "/builds/#{@get('id')}", _method: 'delete'
+    Travis.ajax.post "/builds/#{@get('id')}/cancel"
   )
 
   requeue: ->

assets/scripts/app/models/job.coffee

@@ -73,11 +73,11 @@ require 'travis/model'
   ).property('config', 'build.rawConfigKeys.length')
 
   canCancel: (->
-    @get('state') == 'created' || @get('state') == 'queued' # TODO
+    @get('state') == 'created'
   ).property('state')
 
   cancel: (->
-    Travis.ajax.post "/jobs/#{@get('id')}", _method: 'delete'
+    Travis.ajax.post "/jobs/#{@get('id')}/cancel"
   )
 
   requeue: ->

assets/scripts/app/views/repo/show.coffee

@@ -94,12 +94,30 @@ Travis.reopen
     cancelBuild: ->
       if @get('canCancelBuild')
         @closeMenu()
-        @get('build').cancel()
+        Travis.flash(notice: 'Build cancelation has been scheduled.')
+        @get('build').cancel().then ->
+          Travis.flash(success: 'Build has been successfuly canceled.')
+        , (xhr) ->
+          if xhr.status == 422
+            Travis.flash(error: 'This build can\'t be canceled')
+          else if xhr.status == 403
+            Travis.flash(error: 'You don\'t have sufficient access to cancel this build')
+          else
+            Travis.flash(error: 'An error occured when canceling the build')
 
     cancelJob: ->
       if @get('canCancelJob')
         @closeMenu()
-        @get('job').cancel()
+        Travis.flash(notice: 'Job cancelation has been scheduled.')
+        @get('job').cancel().then ->
+          Travis.flash(success: 'Job has been successfuly canceled.')
+        , (xhr) ->
+          if xhr.status == 422
+            Travis.flash(error: 'This job can\'t be canceled')
+          else if xhr.status == 403
+            Travis.flash(error: 'You don\'t have sufficient access to cancel this job')
+          else
+            Travis.flash(error: 'An error occured when canceling the job')
 
     statusImages: ->
       @set('active', true)
@@ -168,26 +186,22 @@ Travis.reopen
         Travis.Urls.plainTextLog(id)
     ).property('jobIdForLog')
 
-    displayCancelBuild: (->
-      # @get('isBuildTab') && @get('build.canCancel')
-      false
-    ).property('build.state', 'tab')
-
     canCancelBuild: (->
-      # @get('displayCancelBuild') && @get('hasPermission')
-      false
+      @get('displayCancelBuild') && @get('hasPermission')
     ).property('displayCancelBuild', 'hasPermission')
 
-    displayCancelJob: (->
-      # @get('isJobTab') && @get('job.canCancel')
-      false
-    ).property('job.state', 'tab')
+    displayCancelBuild: (->
+      @get('isBuildTab') && @get('build.canCancel')
+    ).property('isBuildTab', 'build.canCancel')
 
     canCancelJob: (->
-      # @get('displayCancelJob') && @get('hasPermission')
-      false
+      @get('displayCancelJob') && @get('hasPermission')
     ).property('displayCancelJob', 'hasPermission')
 
+    displayCancelJob: (->
+      @get('isJobTab') && @get('job.canCancel')
+    ).property('isJobTab', 'job.canCancel')
+
     displayRegenerateKey: true
 
     canRegenerateKey: (->