T321 Add CREATE OR ALTER PROCEDURE support

[makssent]

Fixes #93.

request: CREATE OR ALTER PROCEDURE SUMM (A INTEGER, B INTEGER) RETURNS(C INTEGER) AS BEGIN c = a + b; SUSPEND; END

error message: You have an error in your SQL syntax: CREATE OR ALTER PROCEDURE SUMM (A INTEGER B INTEGER) RETURNS(C INTEGER) AS BEGIN c = a + b; SUSPEND; END no viable alternative at input 'CREATEOR' at line 1 position 8 near @18:9='OR'<99>1:8

NEW err message:
Can not accept SQL type CreateOrAlterProcedureContext.

[makssent]

Нужно добавить ещё поддержку WHILE DO и FETCH, выдает ошибку в тесте: E121-010 
(CREATE OR ALTER PROCEDURE GET_NAMECOMPANY RETURNS (NAMECOM CHAR(30)) AS DECLARE curs1 CURSOR FOR (Select namecompany from Company where typeproduct = 'pc'); BEGIN OPEN curs1; WHILE (1=1) DO BEGIN FETCH curs1 INTO :NAMECOM; IF (ROW_COUNT = 0) THEN LEAVE; SUSPEND; END CLOSE curs1; END;)

[TedCraft]

Тут я бы тоже по аналогии с CREATE OR ALTER TRIGGER сделал сразу три правила, для CREATE, ALTER и CREATE OR ALTER.