Remove AngularJS again

After evaluating AngularJS I came to the decision to drop it again.
AngularJS makes perfectly sense with Rails, but only if AngularJS is
responsible for the whole front-end and not only a part. For this
project or at least with the deadline of my master's thesis in mind I
will drop this idea for now.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Update Bootstrap 3 gem and adjusted project to it

Since Bootstrap 3 was released I have update the gem to the current
version. Some things are still missing, while Bootstrap has moved the
Glyphicons back into the project it is not completely cooperated by the
gem yet. Hence, I will use the added Glyphicon Sass file for now.

Also added some small changes, for instance the height adjustment of a
form control. I don't know from where this is coming, but there is
definitely a height mismatch in Chrome.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Move metric partials into a separate folder

For reasons of better overview I have moved the metric partials into its
own directory.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Implement location hash sensitive tabs

The tab selection of the link checker metric view is now also persisted
in the current window location. If a tab is selected the window location
is changed.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Add record identifier and hyperlinks to table

To provide better verification I have linked the URLs to their actual
destination. In addition, the record identifier is now displayed as
well.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Implement filter search for the link checker page

I have added an input event handling to implement the filter search for
the link checker.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Remove buttons from the link checker page

For now I have removed the buttons of the link checker metric page as it
does not seem to very helpful to display the working links for now. If I
will add it again, then I have to find a more suitable implementation.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Update Bootstrap 3 gems and remove separate font

The Bootstrap 3 gem now supports the Glyphicons once again. Hence, I
have removed the font asset and adjusted some stylesheets accordingly.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>