Exclude some files in jars from packaging.

- Using the new gradle Android plugin 0.7.1:
https://plus.google.com/+AndroidDevelopers/posts/3nf8QErGfcv
Add missing target API annotation.
Use correct Locale for enum conversion.
Drop mindSdk and targetSdk version from manifest.

- Related IDE bug was fixed, can rely only on gradle build script right
now.
Set US locale for TVDb date format.
Fix invalid IDs for search fragment layout.
Make some global fields local variables.

- Also remove some unused fields.
Remove unnecessary semicolons.
Simplify some if statements.
Simplify some conditions.

- Also add NP check in DBUtils.isShowExists().
Drop unneeded return.
Inline some unneeded variables.
Removed empty method.
Dropped unused Exception from throws list.
Drop unneeded method params.
Drop unused return value.
Set exception as ignored for inspection tool.
Drop unused imports, do some formatting.
Use Collections.addAll instead of for each loop.
Use equals to make clear what we compare.