std.string.indexOf with a start index

Basically indexOf with start index. This index is added to the found
index if the searched character was found.

std.string.indexOf(Char1,Char2)(with start index)

The same thing as with the single character indexOf.

fixed the auto-tester complains

save

another bug bites the dust

fix the startIdx problem

std.string.indexOf with a start index

Basically indexOf with start index. This index is added to the found
index if the searched character was found.

std.string.indexOf(Char1,Char2)(with start index)

The same thing as with the single character indexOf.

fixed the auto-tester complains

save

merge error

everything is nicer now

another fix

whitespace formatting

consistency

whitespace args

some more nitpicks fixes

spelling
Merge pull request #1301 from burner/indexOfIdx

std.string.indexOf with start index