Better highlight for repeat count error

Before:
````
test.rs:3:21: 3:30 error: expected constant integer for repeat count but found variable
test.rs:3             let a = ~[0, ..n]; //~ ERROR expected constant integer for repeat count but found variable
                              ^~~~~~~~~
````

After:
````
test.rs:3:27: 3:28 error: expected constant integer for repeat count but found variable
test.rs:3             let a = ~[0, ..n]; //~ ERROR expected constant integer for repeat count but found variable
                                     ^
````
inline the implementation of TotalOrd for integers
auto merge of #5206 : thestinger/rust/cmp, r=brson

minor little performance issue - the vector and string implementations of TotalOrd turn out badly without explicitly inlining this
auto merge of #5198 : youknowone/rust/repeat-count, r=brson

Before:
````
test.rs:3:21: 3:30 error: expected constant integer for repeat count but found variable
test.rs:3             let a = ~[0, ..n]; //~ ERROR expected constant integer for repeat count but found variable
                              ^~~~~~~~~
````

After:
````
test.rs:3:27: 3:28 error: expected constant integer for repeat count but found variable
test.rs:3             let a = ~[0, ..n]; //~ ERROR expected constant integer for repeat count but found variable
                                     ^
````
librustc: Forbid chained imports and fix the logic for one-level renaming imports
librustc: Remove `fn@`, `fn~`, and `fn&` from librustc. rs=defun
libsyntax: Remove `fn@`, `fn~`, and `fn&` from libsyntax. rs=defun
libstd: Remove `fn@`, `fn~`, and `fn&` from libstd. rs=defun
libcore: Remove `fn@`, `fn~`, and `fn&` from libcore. rs=defun
test: Remove `fn@`, `fn~`, and `fn&` from the test suite. rs=defun
librustdoc: Remove `fn@`, `fn~`, and `fn&` from compiletest, fuzzer, rustdoc, and rt. rs=defun
librustc: Stop parsing `fn@`, `fn~`, and `fn&`