Make DeckTask a bit more defensive.

Add an easy way to check things are called from the right task and add
that to DeckTask.

Add an easy way to log methods being called.
Refresh to Travis CI configuration.

This commit updates the Travis Continuous Integration configuration to
make it work again.

I chose a different approach to installing the SDK, that avoid depending
on the order in which things are returned by the tool and breaks each
time something changes (like a new release). Instead use static links to
the SDK components that we need.

Since the continuous build is not reliable enough (or at least I am not
sure it is), also only notify myself of failures.
Remove trailing white-space (once more, i guess.
Use less specific CSS selectors for the default font.

Targetting .question and .answer will override anything set outside of
those, namely .card{}.
Merge remote-tracking branch 'hssm/default-font-selector' into v2.1-dev-ospalh-special-cssfix
Semi-automatically remove some trailing whitespace.
Cause Card.getQuestion to reload the note.
Calling Card.getQuestion with one argument is getQuestion(bool simple), which does not reload the card.
Calling it with just simple=true and then not using the return value seems pointless.
Merge branch 'get-question-reload' into v2.1-dev-ospalh-special
Merge pull request #33 from hssm/default-font-selector

Use less specific CSS selectors for the default font.
Correctly handle calls to constructors.

Make sure we always call the super constructor because they might set a
default style and this would be lost if we call it with zero.
Merge pull request #31 from flerda/v2.1-travis

Refresh to Travis CI configuration.
Merge pull request #35 from flerda/v2.1-preference-constructors

Correctly handle calls to constructors.
Merge pull request #30 from flerda/defensive

Make DeckTask a bit more defensive.
Reformat CardBrowser.java.

This is to actually help merge another file that has been reformatted,
but it is always good to improve our code.
Merge pull request #38 from flerda/v2.1-card-browser

Reformat CardBrowser.java.
Upgrade Gson library to 2.2.3.

This now includes the full distribution, including sources, javadoc, and
README and LICENSE files.
Merge pull request #39 from flerda/v2.1-gson

Upgrade Gson library to 2.2.3.
Merge branch 'v2.1-dev' into v2.1-dev-ospalh-special
A bit of ce.
Rearranged js code a bit.
But code from bottom of card into card.js and wrap in $(document).ready().
Changed brace style in that file.
Renamed img to image. Seems to fix problem with rescaling.