* main.cpp: removed path checking and db loading
 * card database: merge card loading methods into a single one
 * settings cache: take care of returning safe paths for decks,
replays, etc..
 * main window: if db loading fails (eg. first run), propose to run
oracle

NSIS: propose to run cockatrice instead of oracle

Rework card database loading

 * Move carddatabase-related method out of deckeditor tab
 * Load cards in another thread and render them progressively
 * Optimize database reload after enabled sets change

Fix deck editor column width

 * removed the noCard hack.
 * getCard() no more creates cards instead of just returning existing
ones
 * Fix the “edit tokens” dialog.
 * PictureLoader: avoid trying to download twice the same card
 * PictureLoader: correct return of card background
 * AbstractCardItem: avoid recalculating card color at every paint

Use a different file to save custom tokens

Misc required improvements

 * Use nullptr;
 * Refactor CardInfoWidget to use CardInfoPicture and CardInfoText
instead of duplicating code;
 * Added CardInfo::getColorChar()
 * Fixed some potential crashes
 * removed dead code related to CardInfoWidget
 * Don't require a restart after adding a new custom sets file
 * Bump CMake requirements to 3.1

- `sounds` and `themes` moved into `cockatrice/`

moved subdirectory reference
`/cmakelists` to `/cockatrice/cmakelists`

Uses the built in cmake -Dtest=ON

It should download googletest on the fly if needed.

Adds a new make target, `make test`

Ref #167

fix #1547

 * Removed remaining picture handling from card database and cardinfo
 * removed the “noCard object” hack

Use -DPORTABLE=1 to build a portable version

This is the first implementation of a theme manager. It’s a rebased and
revisited version of #792.

 * added missing bits of serverside code;
 * added fronted in client;
 * removed demo python scripts;

This is the first implementation of a theme manager. It’s a rebased and
revisited version of #792.

 * add to the application bundle a custom info.plist
 * fix a graphic glitch on the life counter

 * ignore .tx folder
 * cmake: when UPDATE_TRANSLATIONS=ON, extract new strings only to the
english translation file.
 * added info in CONTRIBUTING.md
 * updated english translations

 * Always install “release” plugins
 * install only plugins actually used

We previously parsed only .cpp files, but some strings are inlined in
header files.

fixes #411

They are needed to fetch prices from deckbrew and possibly, in the
future, for ssl server connections