Add `binary_to_integer/1` and vice versa for pre-R16

Modules which use `binary_to_integer/1` or `integer_to_binary/1` should
include internal header `no_binary_to_integer.hrl` to maintain
backwards compatibility with pre-R16 Erlang versions:

    -include("no_binary_to_integer.hrl").

Once support for those versions is deemed unnecessary
follow these steps to drop it:

- remove `{platform_define, "R1[45]", no_binary_to_integer}`
  from `rebar.config`,
- remove the aforementioned include directive from all relevant
  modules and `no_binary_to_integer.hrl` from the repository,
- remove the `binary_to_integer/1` and `integer_to_binary/1` functions
  from `escalus_utils`.

Since R16+ versions natively support the functions in question
no call sites will have to be modified.
Fix style
Update call sites to use binary_to_integer/integer_to_binary

This requires the compatibility header file `no_binary_to_integer.hrl`.