Test failures in develop with msvc-14.1

This is the list of failures I get right now with msvc-14.1 (VS2017)
```
b2 toolset=msvc-14.1 --abbreviate-paths cxxflags="\wd4244 \wd4996" -j4 test
```

test\algorithms\detail\algorithms_approximately_equals
```
test/algorithms/detail/approximately_equals.cpp(75): error: in "test_main_caller( argc_ argv )": Expected: 54 Detected: 43
test/algorithms/detail/approximately_equals.cpp(75): error: in "test_main_caller( argc_ argv )": Expected: 44 Detected: 33
test/algorithms/detail/approximately_equals.cpp(75): error: in "test_main_caller( argc_ argv )": Expected: 34 Detected: 23
```

test\algorithms\overlay\algorithms_get_clusters
```
test/algorithms/overlay/get_clusters.cpp(67): error: in "test_main_caller( argc_ argv )": Case: borderx_no ctype: e expected: 0 detected: 1
test/algorithms/overlay/get_clusters.cpp(67): error: in "test_main_caller( argc_ argv )": Case: bordery_no ctype: e expected: 0 detected: 1
```

test\algorithms\overlay\algorithms_sort_by_side
```
test/algorithms/overlay/sort_by_side.cpp(215): error: in "test_main_caller( argc_ argv )": caseid=case_recursive_boxes_46_union open count: expected=[2 , 1 , 2 , 1 , 1 , 2 , 1] detected=[2 , 1 , 1 , 2 , 1 , 2 , 1]
```

----

FIXED:

test\algorithms\algorithms_line_interpolate
https://github.com/boostorg/geometry/pull/854
```
test/algorithms/line_interpolate.cpp(60): error: in "test_main_caller( argc_ argv )": MULTIPOINT((1.4 1),(1.8 1),(2 1.2),(2 1.6),(2 2),(1.6 2),(1.2 2),(1 2.2),(1 2.6),(1 3)) != MULTIPOINT((1.4 1),(1.8 1),(2 1.2),(2 1.6),(2 2),(1.6 2),(1.2 2),(1 2.2),(1 2.6))
test/algorithms/line_interpolate.cpp(60): error: in "test_main_caller( argc_ argv )": MULTIPOINT((1.8 1),(2 1.6),(1.6 2),(1 2.2),(1 3)) != MULTIPOINT((1.8 1),(2 1.6),(1.6 2),(1 2.2))
test/algorithms/line_interpolate.cpp(60): error: in "test_main_caller( argc_ argv )": MULTIPOINT((1.79997 1.00002),(2 1.59985),(1.60006 2.00007),(1 2.20015),(1 3)) != MULTIPOINT((1.79997 1.00002),(2 1.59985),(1.60006 2.00007),(1 2.20015))
```

test\algorithms\overlay\algorithms_get_clusters
https://github.com/boostorg/geometry/pull/878
```
test\algorithms\overlay\get_clusters.cpp(82): error C2398: Element '3': conversion from 'initializer list' to '_Ty' requires a narrowing conversion
with
[
_Ty=fp
]
test\algorithms\overlay\get_clusters.cpp(82): error C2398: Element '1': conversion from 'double' to 'const CoordinateType &' requires a narrowing conversion
with
[
CoordinateType=float
]
test\algorithms\overlay\get_clusters.cpp(83): error C2398: Element '3': conversion from 'initializer list' to '_Ty' requires a narrowing conversion
with
[
_Ty=fp
]
test\algorithms\overlay\get_clusters.cpp(83): error C2398: Element '1': conversion from 'double' to 'const CoordinateType &' requires a narrowing conversion
with
[
CoordinateType=float
]
test\algorithms\overlay\get_clusters.cpp(84): error C2398: Element '3': conversion from 'initializer list' to '_Ty' requires a narrowing conversion
with
[
_Ty=fp
]
test\algorithms\overlay\get_clusters.cpp(84): error C2398: Element '1': conversion from 'double' to 'const CoordinateType &' requires a narrowing conversion
with
[
CoordinateType=float
]
test\algorithms\overlay\get_clusters.cpp(85): error C2398: Element '3': conversion from 'initializer list' to '_Ty' requires a narrowing conversion
with
[
_Ty=fp
]
test\algorithms\overlay\get_clusters.cpp(85): error C2398: Element '1': conversion from 'double' to 'const CoordinateType &' requires a narrowing conversion
with
[
CoordinateType=float
]
```