Allowing 'F' mode for 1 channel FloatTensor

[surgan12]

fixes #1099
cc: @fmassa

[codecov-io]

Codecov Report

Merging #1100 into master will increase coverage by 0.09%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1100      +/-   ##
==========================================
+ Coverage   64.57%   64.66%   +0.09%     
==========================================
  Files          68       68              
  Lines        5411     5411              
  Branches      831      831              
==========================================
+ Hits         3494     3499       +5     
+ Misses       1665     1662       -3     
+ Partials      252      250       -2

Impacted Files	Coverage Δ
torchvision/transforms/functional.py	71.38% <100%> (ø)	⬆️
torchvision/transforms/transforms.py	81.53% <0%> (+0.98%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 3483342...0227db5. Read the comment docs.

[fmassa]

Thanks!