restrict: better offset support

[johnnychen94]

Two things are included in this PR:

1. relax require_one_based_indexing constrain via eagerly collect; this helps handle edge cases such as SubArray with offsets and others.
2. OffsetArray performance was not good because there was unnecessary offset computation in the internal for loop. By eagerly convert it to the non-offsetted array before passing to restrict, the overhead is removed.

using ImageBase, TestImages, OffsetArrays

img = testimage("camera");
imgo = OffsetArray(img, -1, -1);

@btime restrict($img);
# 90.136 μs (10 allocations: 772.31 KiB)

@btime restrict($imgo);
# master: 211.889 μs (14 allocations: 772.53 KiB)
# PR: 89.594 μs (10 allocations: 772.31 KiB)

[codecov]

Codecov Report

Merging #9 (69d90bc) into master (1eb0a79) will decrease coverage by 0.85%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master       #9      +/-   ##
==========================================
- Coverage   92.85%   92.00%   -0.86%     
==========================================
  Files           3        3              
  Lines         126      125       -1     
==========================================
- Hits          117      115       -2     
- Misses          9       10       +1     

Impacted Files	Coverage Δ
src/restrict.jl	96.63% <100.00%> (-0.03%)	⬇️
src/compat.jl	0.00% <0.00%> (-100.00%)	⬇️

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