Updated Android introductory tutorials, based on frequent Q&A questions/issues.
Wrote script generating timing table
Improved code
OpenCV example-tutorial1 does not work on Android emulator (Bug #2656)

Problems with Android 2.3.3 (API level 10) fixed;
Android 2.2 does not work due to unsupported camera frame format (known android-2.2 emulator issue).
OpenCV Manager crashes with exception (Bug #2660)

String checking and range cheching added.
modify default css for search button (error #2654)
updating tutorial #1
Merge pull request #260 from alekcac:css_fix
Merge ppull request #258 from asmorkalov/android_emu_fix
Merge pull request #259 from asmorkalov:manager_outofbound_fix
Merge pull request #257 from AnnaKogan8:perf-tests-timing-script
updating tutorial #2
Merge pull request #247 from wswld:2.4
Updated readme.txt with desciption about different OCV Manager packages
hiding empty menu button on Android 4
Updated OpenCV Manager rst documentation
Explicitly use double precision sin & cos in hough implementation

On some platforms sin and cos are calculated in single precision resulting in
diversity of results.
Merge pull request #262 from kirill-kornyakov:minor-cleanings-for-android-sdk
Merge pull request #261 from apavlenko:samples_remove_empty_menu
Merge pull request #263 from taka-no-me:hough_explicit_double