Change symbol for inclusive range (...) to keyword to to disambiguate from open range (..), and change ranged for to use inclusive ranges

[expikr]

current:

usage	a..	a..b	a...b
switch	no	no	yes
ranged for	no	yes	no
indexed for	yes	yes	no
slice	yes	yes	no

proposed:

usage	a..	a..b	(a to b)
switch	no	no	yes
ranged for	no	(no)	(yes)
indexed for	yes	(no)	no
slice	yes	yes	no

Since ranged for do not permit unbounded ranges, there is no reason to use a syntax that allows it.

switch(a) {
    0 to 10 => {
        // top ten
    },
    69 => {
        // nice
    },
    else => {
        if(a<100} {
            // inside ranking
        } else {
            // outside ranking
        }
    },
}

for(0 to 10) {
    // 11 steps executed
}

for(items, 0..) |item, i| {
    // iterate all
}

for(items[2..9], 10..) |item, i| {
    // item[2] , 10
    // item[3] , 11
    // etc
}

[BratishkaErik]

See #359 (comment)

[andrewrk]

Not interested in language proposals