Bump test coverage to 100%

[sanmai]

Here's what PHPUnit said before the most of the commits:

 Summary:                  
  Classes: 16.67% (1/6)    
  Methods: 90.24% (111/123)
  Lines:   97.27% (677/696)

\YaLinqo::EnumerableGeneration
  Methods:  94.74% (18/19)   Lines:  95.65% ( 66/ 69)
\YaLinqo::EnumerablePagination
  Methods:  95.45% (21/22)   Lines:  99.29% (139/140)
\YaLinqo::YaLinqo\Enumerable
  Methods:  98.25% (56/57)   Lines:  99.63% (268/269)
\YaLinqo::YaLinqo\Functions
  Methods:  14.29% ( 1/ 7)   Lines:  79.31% ( 23/ 29)
\YaLinqo::YaLinqo\OrderedEnumerable
  Methods: 100.00% (13/13)   Lines: 100.00% ( 99/ 99)
\YaLinqo::YaLinqo\Utils
  Methods:  40.00% ( 2/ 5)   Lines:  88.71% ( 55/ 62)

For one reason this could be because PHPUnit was or even is picky about braces around conditionals. These brace-less ifs are everywhere in the code. In earlier versions of PHPUnit they could be reported as covered even if they aren't.

Here's what it says now:

 Summary:                   
  Classes: 100.00% (6/6)    
  Methods: 100.00% (121/121)
  Lines:   100.00% (680/680)

\YaLinqo::EnumerableGeneration
  Methods: 100.00% (18/18)   Lines: 100.00% ( 64/ 64)
\YaLinqo::EnumerablePagination
  Methods: 100.00% (22/22)   Lines: 100.00% (138/138)
\YaLinqo::YaLinqo\Enumerable
  Methods: 100.00% (57/57)   Lines: 100.00% (266/266)
\YaLinqo::YaLinqo\Functions
  Methods: 100.00% ( 7/ 7)   Lines: 100.00% ( 29/ 29)
\YaLinqo::YaLinqo\OrderedEnumerable
  Methods: 100.00% (13/13)   Lines: 100.00% ( 99/ 99)
\YaLinqo::YaLinqo\Utils
  Methods: 100.00% ( 4/ 4)   Lines: 100.00% ( 56/ 56)

See for yourself.

Also it should now actually test on PHP 7+. Earlier it used a Travis-provided version of PHPUnit which was't always working as one can expect.

[Athari]

@sanmai Sorry for taking so long to respond. I'm not dead, I'm just busy. I'll try looking into it later this week.

[sanmai]

Hey! Thanks for getting back. No worries, take your time.