The gotest parser used a bufio.Scanner to read its input, which
prevented us from reading lines larger than 64K.
In order to support reading larger lines, bufio.Scanner has been
replaced with bufio.Reader. The maximum line size has been increased to
4MiB and instead of returning an error when reading lines that exceed
the maximum size, we truncate that line and continue parsing.
Fixes#135
The reportBuilder has been updated to use the ordered output collector
to keep track of go test output. This makes it possible to include
benchmark output in the generated report and makes sure that output is
preserved when deleting subtest parents from the report.
