Almost all test scripts currently need to override the __init__()
method. When they do that they need to call into super().__init__() as
the base class does some generic initialization.
This commit makes the base class __init__() call into set_test_params()
method. Individual test cases can override set_test_params() to setup
their test parameters.
English grammar dictates that these bullet points should be capitalized.
This also makes the capitalization style consistent with the rest of the
document, e.g. the "Decision Making Process" section.
maxblocksinflight tested that a node would not send get_data messages
for more than 16 new blocks at the same time. bitcoin core no longer
responds to block invs with get_data, since it does headers-first
sync'ing. This test was therefore testing nothing and can be removed.
the sendheaders test script tests that bitcoin will not send get_headers
for more than 16 blocks simultaneously.