dg1d: update `lgl` and `glgl` integration methods

• put the integrand as the first argument
• add integration methods that can work with a function argument
• add doc strings
• update usage of integrate functions in rest of code

added analysis refactor labels

added 1 commit

• 45d42023 - slap on some abstract type constraints

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added 2 commits

• 382dd60b - fixes
• c4ef7eba - a unit test for integrate

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added 5 commits

• e2b1a670 - 1 commit from branch main
• e88ea7f2 - update lgl and glgl integration methods
• 0bfdc09b - slap on some abstract type constraints
• bad9ccfc - fixes
• 39bd0a32 - a unit test for integrate

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merged

mentioned in commit 1d78c8f6

mentioned in merge request !211 (merged)

mentioned in commit cd4a82d6