Closes Issue#39, App now has fetch functionality via a button on the app bar

[nathangavin]

Closes issue #39.

Changes made to the app include adding a 'sync' button to the top of the screen. when this button is pressed, the user is presented with a dialog which asks the user for the URL of the original repository they wish to sync. Then the app runs the various commands to establish the local remote repository, then pulling and merging from there, Also, the user is informed when the synchronization process as begun and has finished.

files edited:

• app/components/header.component.ts
  • app/misc/git.ts

files added:

• assets/refresh-button.png

[Scoobster]

@softeng-701 tagging for approval and merge

[softeng-701]

@nathangavin @Scoobster Please squash your commits before the deadline. Also, make sure all group members have given their reviews. Thanks!

[softeng-701]

Looks good! Will merge after the deadline

[nathangavin]

@softeng-701 commits have been squashed, though doing the squash required a merge, creating a new commit. All group members have approved the code.