PHP 5.x compatible release

* Added Nexus test suite (serbanghita#581)
* Add Samsung SM-G892A, SM-A530F (serbanghita#834)
* Add Xiaomi phone model (serbanghita#841)
* Add Xperia XZ serials (serbanghita#816)
* Added PhpDoc tags to help autocomplete magic calls in IDEs (serbanghita#768)
* Added script to generate methods names in PHPDoc
* New tablets (from Anne Jan) (serbanghita#851)
* Samsung Tab A7 SM-T500 not recognized as tablet (serbanghita#853)

* Samsung Galaxy Tab S7+ detected as Phone instead of Tablet type: ne…

…w User-Agent strings (serbanghita#850)

* Google Pixel should have own category status: pending research type: new User-Agent strings (serbanghita#815)
* Edge on iOS 12 is detected as Safari type: bug type: new User-Agent strings (serbanghita#764)
* Pixel 2 phone device mis-detected as Galapad tablet device type: bug type: new User-Agent strings (serbanghita#761)

Huawei AspiegelBot type: new User-Agent strings serbanghita#835

Two Samsung tablets id as phones type: new User-Agent strings serbanghita#846
Add Sailfish OS and Sailfish Browser to the detection list and tests serbanghita#784
Samsung tablets type: new User-Agent strings serbanghita#81
3rd generation iPad Pro. and it returns this is a computer type: new User-Agent strings serbanghita#827
WebP image support status: invalid type: question serbanghita#828
Fixed PHP 7.4: Trying to access array offset on value of type null  PHP7 type: bug serbanghita#830
Add new SM-G981B Samsung phone user-agent type: new User-Agent strings type: question serbanghita#836
Update Facebook Bots User Agents area: Documentaion serbanghita#837
Detecting desktop version in IOS? type: question serbanghita#845
xiaomi 8pro not detected as mobile status: invalid serbanghita#849

https://github.com/serbanghita/Mobile-Detect/milestone/26

Sony Xperia Z4 Tablet SGP771 is not detected as tablet (serbanghita#753)

Google Pixel 2 is detected as tablet (serbanghita#750)
Samsung GT-P5100 is detected as mobile (serbanghita#743)
Chrome 66 detected as Opera (serbanghita#738)
Mediacom tablets are not parsed as tablets (serbanghita#733)
Onda V10 tablet is detected as phone (serbanghita#729)
Lenovo Tab2 TB2-X30L is detected as phone (serbanghita#725)

New tablets and devices from users.

Added missing samsung tablet SM-T585 (serbanghita#712)

Lenovo Tab4 10 tablet is detected as phone (serbanghita#716)
New 3rd party module (serbanghita#714)
HUAWAI P8 phone recognized as UnknownTablet (serbanghita#711)
Asus Zenpad 8.0 (P024) should be a tablet (serbanghita#709)
Reorganizing the PHPCS rules for 2.x
Reorganized text. Added new info about desktops

Add Lenovo Mobiles (serbanghita#706)

Tablets of brand bq: regexp causes Catastrophic backtracking.(serbanghita#605)
Pixel phone support (serbanghita#610, serbanghita#611)
Moto X 2nd Gen (serbanghita#612, serbanghita#613)
Lenovo Tab3 8 Plus TB-8703F not detected as tablet (serbanghita#704)
AppleCoreMedia user agent on iPhone and iPad devices
is not recognized as iOS device when the client is requesting html5 video data (serbanghita#620)
Maybe inconsistency regarding "UC Browser" (serbanghita#451)
Use PHPUnit\Framework\TestCase instead of PHPUnit_Framework_TestCase (serbanghita#702)

* Improved readme files

* Added new Huawei, Lenovo, Samsung devices
* New Verizon test file.

Add .Net port (serbanghita#698)

hgoebl/mobile-detect.js#67 - Limited UA string to max 500 chars to protect from DoS
Added Samsung devices.
Added new HTC device. Updated regex to be less eager.
New Slack chat badge.
Add PHP 7.1 and 7.2 to Travis test matrix (serbanghita#680)
Turned on coverage reporting.