Add more test combinators

• Add boolean assert: Alcotest.bool (#33, by @zjhmale)
• Add sorted list assert: Alcotest.slist (#34, by @samoht)
• Add pair assert: Alcotest.pair (#34, by @samoht)
• Add simple assert, built using Pervasive.compare and a pretty-printing
  function: Alcotest.of_pp (#34, by @samoht)

Fix regressions

• Fix of the format of log filenames
• Fix a regression in 0.4.* which were hiding error messages when using wrong
  command-line arguments

Flush display and UTF8 documentation strings

• Flush formatter for Alcotest.check (#27, by @edwintorok)
• Handle UTF8 for test documentation strings (#5)

Better looking outputs

• Improve the result outputs

Fix error reporting

• Fix regression introduced in 0.4.0: display the error if there is only one error
• Add a testable combinator for options.

Remove dependency to OUnit, add `TESTABLE` combinators

• Simplify the use of the library by removing global states -- now calling
  the run function multiple times is much more consistent.
• Remove the direct dependency to OUnit. Programs using OUnit and Alcotest
  should continue to work.
• Add a TESTABLE signature and a check function to check invariants in
  the tested libraries.

Add a JSON output, allow to call multiple `run` in a program.

• Control --show-errors using the ALCOTEST_SHOW_ERRORS env variable (#9)
• Add an and_exit optional argument to Alcotest.run to control
  the exit behavior of the main test function (#4)
• Fix the output of --version
• Add a --json argument to show the test results as a JSON object
  (#14, by @leowzukw)
• Expose Alcotest.result to turn a test into a result

Add a logo, a simple example, and try to not fail if the output file does not exist

• Do not fail if the output file does not exist
• Add a simple example (#10, by @leowzukw)
• Add a logo (#12, by @leowzukw)

Fix OCaml 4.01 regression support and and Travis tests

• Fix OCaml 4.01.0 and earlier support (regressed in 0.3.0).
• Add Travis CI tests.

Fix backtrace and use Bytes instead of String

• Fix backtrace handling (#2 by @dsheets)
• Use Bytes module instead of String