Cleanup for Finder.java. Update up to libanki 2.0.26.

- Moved add function into existing SearchState convenience class. Avoids passing itself as a parameter and is now contained in the only place it's used.
- Added missing search commands (_findCids, _findDupes).
- Moved AnkiDroid-specific code into own functions at bottom of file.
- Overload _order instead of unreliable check for "true" string.
- _findDeck() checks if did is already contained in wildcard search (python version uses set which guarantees uniqueness automatically)

Contains these commits from dae/anki:

- support cid:<card id> search (https://github.com/dae/anki/commit/013f879d4e6a5cc503e3650edc97baaf7d818a0b)
- strip html in duplicate check (https://github.com/dae/anki/commit/4d42282b7b435e7ac0c8840f26ec89fa3da63701)
- escape + in deck names (https://github.com/dae/anki/commit/26a3c30365c3d8fc0dfbd7d9782e34131f8f484b)
- fix find dupes when fieldname case differs (https://github.com/dae/anki/commit/5db00d58158280c2e01ef5fa7e686b2792e168dc )
- fix duplicate search in browser (https://github.com/dae/anki/commit/3f6266a7123b23f14a593d34e0cc3287e10e689f)
- failure to find a field should not break entire query (https://github.com/dae/anki/commit/b571a4caa85bebf5a736ac1789b3ec4a51386631)
Merge pull request #369 from hssm/libanki-cleanup-update-2.0.25

Cleanup for Finder.java. Update up to libanki 2.0.26.
Remove random zero-width non-breaking spaces (UTF-8 encoded BOMs).
Fix a typo, use an en dash.
Suggested by lint.
Use ellipsis character (…) instead of three dots.
Don’t say please.
Reworded other texts. Less wordy. Important bits firs.
All per  Android style guide. https://developer.android.com/design/style/writing.html
Put negative buttons to the left starting with API 14, the way they should https://developer.android.com/design/building-blocks/dialogs.html .
Also removed a bit of trailing white space and fixed a typo in javadocs.
Replaced Yes and No in dialog buttons with more precise term and Cancel.
Some more clean-up of texts. Removed bits of fluff like "successfully".
Use sp, not dp for text sizes.
Suggested by lint.
Use sentence case, contractions, following the Android writing style guide.
Dto. Use of periods. No for one sentence, one per sentence if more then one.
Also joined identical string constats.
Add description to the image buttons. Used by screen readers.
Set backup to on in manifest. Suggested by lint.
Fix in code: a layout parameter has changed its name from FILL_PARENT to MATCH_PARENT between API 7 and 8
Also clean bits that are possibly unused.
Ignore lint warning here. Those buttons look strange as buttonbar buttons.
Make dialogs buttons look more like in other apps, at least for API >=14 (where we start with Cancel on the left.) (They still have an extra border.)
Make using italic, light and oblique fonts work in Turkey.
Fixes for DefaultLocale lint warning.
Don't reuse a button. Lint comlained.
Made the sound Hadler static.
Probably not a big problem, but suggested by lint.
Make a few more strings translatable. Don’t complain that “1” is not.
Register the GraphicalActivity (statistics)
Remove an unused xml namespace.
Remove title from some dialogs that don't need one.